STRESSFUL LIFE EVENTS,
MODIFIABLE LIFESTYLE FACTORS,
DEPRESSIVE SYMPTOMS,
HEALTH-RELATED QUALITY OF LIFE,
AND CHRONIC DISEASE
AMONG OLDER WOMEN
IN VIETNAM AND AUSTRALIA:
A CROSS-CULTURAL COMPARISON
Dao Tran Tiet Hanh
BNS, BA, MNS, MAppSc. (research)
Prof. Helen Edwards Dr. Charrlotte Seib Prof. Debra Anderson Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy School of Nursing Faculty of Health Queensland University of Technology 2017
Keywords
Australia
Chronic disease: Hypertension, Coronary heart disease, Type 2 diabetes,
Stroke, Arthritis, Osteoporosis, Breast cancer, Depression
Cross-cultural comparison
Depressive symptoms
Diet: Vegetable consumption, fruit consumption
Exercise
Health-related quality of life
Mental health
Modifiable lifestyle factors: Vegetable and fruit consumption, smoking, alcohol and caffeine drinking, physical activity level, exercise, body max index
Older women
Perceived stress
Physical activity
Physical health
Sleeping disturbance
Social support
Stressful life events
Structural Equation Modelling
Vietnam
i
Abstract
There has been a dramatic increase in the number of older people all over the world. Older people usually experience lower health-related quality of life
(HRQOL), and an increased number of chronic conditions than those in younger age groups. Among older people, women appear to be more vulnerable to stress, to have different lifestyles, lower HRQOL and higher risk for certain chronic conditions than men. These areas need more concern in healthcare.
Exposure to stressful life events (SLEs) contributes to changes in lifestyle, to the development of depressive symptoms, and consequently to decreased health. This pattern has been investigated in several populations, including older Australian women, but few studies have modelled the impact of SLEs on health. Vietnamese older women have different culture, historical and socio-economic changes than
Australian women, and this may influence their lifestyle and health. Knowledge about their SLEs, social support, modifiable lifestyle factors, depressive symptoms,
HRQOL, and chronic disease is still unclear.
This research investigated SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic diseases as experienced by older women in Vietnam. The research also explored the impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic diseases and the role of perceived stress and social support on the relationship between SLEs and health among older women in Vietnam. Finally, the research compared findings about SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease from the Vietnamese dataset with those from an Australian dataset.
This research included three studies: (1) A pilot study, which developed the
Vietnamese versions of the research instruments and tested their translation
ii
equivalence and psychometric properties on Vietnamese older women (n=33); (2) A cross-sectional study, which investigated SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam (n=440); and (3) A cross-cultural comparison study of SLEs, modifiable lifestyle, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and Australia (n=624).
This research found that the Vietnamese and Australian older women were exposed to SLEs differently. Compared to the Australians, the Vietnamese reported lower likelihood of healthy eating, consuming alcohol and caffeine, smoking tobacco and exercise. However, Vietnamese reported more sleep problems, major depressive symptoms, lower physical health, and more chronic conditions. The prevalence of stroke, T2DM, arthritis, and osteoporosis among the Vietnamese were similar to those among the Australians. However, the Vietnamese older women were more likely to have high blood pressure and coronary heart disease, but less likely to have obesity and breast cancer than those in Australia. This research also found that exposure to SLEs could influence health, especially mental health, through several pathways. The patterns by which SLEs influenced health were different for the older women in Vietnam and Australia. Perceived stress had stronger influences on health than SLEs. Perceived stress also mediated the impact of the SLEs on diet habits, sleep disturbance, depressive symptoms, and mental health. Social support reduced impact of SLEs on perceived stress, depression and mental health.
Despite the limitations, findings from this research highlighted the importance of interventions to manage stress and promote healthy lifestyle and health, and to support chronic disease management for healthier ageing among older women. The
iii
implications gained from this research can be useful for other Asian and Western countries that have similar characteristics to the study research populations.
iv
Related publications, presentations, awards, and certificates
PEER-REVIEWED JOURNAL PAPERS
Seib, C., Whiteside, E., Lee, K., Humphreys, J., Dao Tran, T. H., Chopin, L.,
& Anderson, D. (2014). Stress, lifestyle, and quality of life in midlife and older
Australian women: Results from the Stress and the Health of Women Study.
Women's Health Issues, 24(1), e43-52. doi:10.1016/j.whi.2013.11.004
Dao-Tran, T.-H., Anderson, D., & Seib, C. (2017). The Vietnamese version of the Perceived Stress Scale (PSS-10): Translation equivalence and psychometric properties among older women. BMC Psychiatry, 17, 53. doi.org/10.1186/s12888-
017-1221-6
Dao Tran, T.H., Anderson, D., Seib, C. (2016) How do stressful life events impact on modifiable lifestyle, depressive symptoms, physical and mental health among Vietnamese older women? BMC Psychiatry, under review
Dao Tran, T.H., Anderson, D., Lee, J., Seib, C. (2017) Personal characteristics, lifestyles, chronic diseases and health-related quality of life of
Vietnamese older women. BMC Women’s health, under review
Dao Tran, T.H., Seib, C. (2016) Prevalence and correlates of sleep disturbance among Vietnamese older women. Journal of Clinical Nursing, under review
CONFERENCE PRESENTATIONS
Dao Tran, T.-H., Seib, C. & Anderson, D., (2015). Stressful life events and health among elderly women in Vietnam. Oral presentation at The Aging & Society:
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The Fifth Interdisciplinary Conference, Washington D.C., USA from November 5 to
6, 2015.
Dao Tran, T.-H., Anderson, D., & Seib, C. (2016). The impact of stressful life events on modifiable lifestyle factors, depressive symptoms, and general health among Vietnamese older women. Oral presentation at Faculty of Health Three
Minute Thesis (3MT) Competition 23/8/2016.
Dao Tran, T.H., Nguyen, P., Seib, C. (2016) Prevalence and correlates of depression among Vietnamese older women. Oral presentation at Hội nghị khoa học kỹ thuật thường niên lần thứ 33 năm 2016, HCMC, Vietnam, 28/10/2016. Published in Tạp chí hội nghị khoa học kỹ thuật thường niên lần thứ 33 năm 2016, HCMC,
Vietnam
Dao Tran, T.-H., Anderson, D., & Seib, C. (2016). Sleeping disturbance among older women in Vietnam: Results from the Vietnamese Women’s Wellness
Research Program. Oral presentation at the 21st International Council on Women’s
Health Issues (ICOWHI) Congress, in Baltimore, Maryland, USA, from November 6 to 9, 2016.
AWARDS
1-3/2017 Write-up scholarship award awarded by Queensland University of
Technology for writing publiscation
9/2015 Queensland University of Technology Grant-in-Aid (Travel Grant),
providing $2000 AUD to travel for overseas conference presentation.
8/2015 Graduate Scholar Awards awarded by “The Aging & Society: The
Fifth Interdisciplinary Conference, Washington D.C, USA,”
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providing a conference fee waiver, an opportunity to chair the
conference parallel sessions, and to provide technical assistance in the
sessions, besides presenting my own research paper.
2013-2016 Queensland University of Technology Postgraduate Research Award
(QUTPRA), providing tuition fee waiver, and living allowance for
PhD study in the School of Nursing, Queensland University of
Technology, Brisbane, Australia.
CERTIFICATES
Certificate of completion of the Sessional Career Advancement Development
(SCAD) Program (17-24/3/2015) from QUT Human Resources Department
Certificate of completion of the “Leadership and Communication” course
(5/2015) from ANT LEAP–Learning employment aptitudes program
Certificate of completion of the “Project Management” course (5/2015) from
ANT LEAP–Learning employment aptitudes program
Certificate of completion of Teaching Advantage Program (11/2016) from
QUT Learning and Teaching
vii
Table of Contents
Keywords ...... i Abstract ...... ii Related publications, presentations, awards, and certificates ...... v Table of Contents...... viii List of Figures ...... xi List of Tables ...... xii List of Abbreviations ...... xiii Statement of Original Authorship ...... xv Acknowledgements...... xvi CHAPTER 1: INTRODUCTION ...... 1 1.1 Background ...... 1 1.2 Research aim and objectives ...... 6 1.2.1 Overall aim ...... 6 1.2.2 Specific objectives ...... 6 1.3 Research questions ...... 7 1.4 Scope of the research ...... 8 1.5 Significance of the study ...... 9 1.6 Definitions of variables ...... 10 1.7 Thesis structure ...... 12 CHAPTER 2: LITERATURE REVIEW ...... 16 2.1 Overview of Vietnam and Australia ...... 16 2.2 Health issues associated with ageing and gender ...... 19 2.3 Health-related quality of life, chronic disease and their determinants ...... 22 2.3.1 Health-related quality of life and its determinants...... 22 2.3.2 Chronic disease and its determinants ...... 26 2.4 PsYchosocial stress and health ...... 35 2.4.1 Stress: definition and the impact on health ...... 35 2.4.2 Mechanisms by which stressful life events influence health ...... 37 2.4.2.1 Stressful life events influence health through physiological changes ...... 38 2.4.2.2 Stressful life events influence health through unhealthy lifestyles ...... 39 2.4.2.3 Stressful life events influencing on health through negative affection ...... 40 2.4.2.4 The roles of social support and perceived stress in the relationship between stressful life events and health ...... 41 2.5 The study’s theoretical framework ...... 43 2.6 HEALTH AND SAFETY STATEMENT, AND ETHICAL APPROVALS ...... 46 2.7 SumMary ...... 48 CHAPTER 3: RESEARCH METHODS – STUDY 1 ...... 51 3.1 Design, setting, sample and sampling method ...... 51
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3.2 Research instruments ...... 52 3.2.1 Socio-demographic characteristics ...... 52 3.2.2 Stressful life events and perceived stress ...... 53 3.2.3 Social support ...... 56 3.2.4 Modifiable lifestyle factors ...... 57 3.2.5 Depressive symptoms, health-related quality of life, and chronic disease ...... 58 3.3 Process to develop the Vietnamese versions of the instruments ...... 60 3.4 Procedure to collect data ...... 63 3.5 Data management and analysis ...... 65 3.6 Summary ...... 69 CHAPTER 4: TRANSLATION EQUIVALENCE AND PSYCHOMETRIC PROPERTIES OF THE VIETNAMESE VERSIONS OF THE RESEARCH INSTRUMENT: RESULTS OF STUDY 1 70 4.1 Translation equivalence, face validity of the Vietnamese versions of the instruments, and study feasibility ...... 70 4.2 The internal consistency and test-retest correlation reliabilities of the Vietnamese version of the instruments ...... 72 4.3 Summary ...... 78 CHAPTER 5: RESEARCH METHODS – STUDY 2 ...... 79 5.1 Design, setting, sample and sampling method ...... 79 5.1.1 Design ...... 79 5.1.2 Setting ...... 80 5.1.3 Sample and sampling methods ...... 80 5.2 Research instrument, procedure for data collection, plan for data management and analysis .. 82 5.3 Summary ...... 85 CHAPTER 6: STRESSFUL LIFE EVENTS, PERCEIVED STRESS, SOCIAL SUPPORT, MODIFIABLE LIFESTYLE FACTORS, DEPRESSIVE SYMPTOMS, HEALTH-RELATED QUALITY OF LIFE, AND CHRONIC DISEASE AMONG OLDER WOMEN IN VIETNAM: RESULTS OF STUDY 2...... 86 6.1 Descriptions ...... 87 6.1.1 Socio-demographic characteristics ...... 87 6.1.2 Stressful life events ...... 88 6.1.3 Social support ...... 95 6.1.4 Modifiable lifestyle characteristics ...... 95 6.1.5 Depressive symptoms, health-related quality of life, and chronic disease ...... 99 6.2 Modelling the impact of stressful life events on modifiable lifestyle factors, depressive symptoms, health related quality of life, and chronic disease among older women in Vietnam ...... 100 6.3 Summary ...... 109 CHAPTER 7: RESEARCH METHODS – STUDY 3 ...... 113 7.1 The relationship of current research with HOW4 ...... 114 7.2 Plan for data analysis ...... 116 7.3 Summary ...... 117 CHAPTER 8: CROSS-CULTURAL COMPARISONS: RESULTS OF STUDY 3 ...... 119 8.1 Comparisions of socio-demographic characteristics ...... 120 8.2 Comparision of stressful life events ...... 120 8.3 Comparisions of modifiable lifestyle factors ...... 124
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8.4 Comparisons of depressive symptoms, health-related quality of life, and chronic disease...... 126 8.5 Model comparisons ...... 126 8.5.1 The influence of SLEs on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam ...... 131 8.5.2 The influence of stressful life events on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Australia ...... 135 8.6 Summary of the findings of study 3 ...... 140 CHAPTER 9: DISCUSSION AND CONCLUSION ...... 142 9.1 The Vietnamese versions of the research instruments ...... 143 9.2 The cross-cultural comparisons ...... 146 9.3 The influence of stressful life events on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic diseases among older women in Vietnam and Australia ...168 9.4 Perceived stress, social support, and their roles on the relationship between stressful life events and health ...... 172 9.4.1 Perceived stress among older women in Vietnam and its mediation roles ...... 172 9.4.2 Social support among older women in Vietnam and its buffering roles ...... 174 9.5 Strengths and limitations of the study ...... 176 9.5.1 Strengths ...... 176 9.5.2 Limitations ...... 178 9.6 Recommendations for future research and implications for healthcare practice and policy ....182 9.6.1 Recommendations for future research ...... 184 9.6.2 Implications for healthcare practice and policy ...... 186 9.7 Conclusion ...... 191 Appendix A: Ethical approval in Vietnam ...... 194 Appendix B: Ethical approval in Australia...... 195 Appendix C: Permission letter to derive HOW4 data (2012) for secondary data analysis ...... 196 Appendix D: QUT Postgraduate Award ...... 197 Appendix E: QUT Grant in Aid Award ...... 198 Appendix F: Graduate Scholar Award ...... 199 Appendix G: Write up scholarship award ...... 201 Appendix H: Certificate of completion “Teaching Advantage Program” ...... 202 Appendix I: Certificate of completion “Leadership and Communication Module” ...... 203 Appendix J: Certificate of completion “Project Management Module” ...... 204 Appendix K: Questionnaire (English version to collect data in Vietnam)...... 205 Appendix L: Results of the test of normality ...... 223 Appendix M: Accepted abstracts for oral conference presentations ...... 225 References ...... 229
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List of Figures
Figure 2.1: Relationships among stressful life events, physiological changes and health ...... 39 Figure 2.2: Relationships among stressful life events, modifiable lifestyle factors, and health ...... 40 Figure 2.3: Relationships among stressful life events, depression and health ...... 41 Figure 2.4: Relationships among stressful life events, social support, perceived stress and health ...... 42 Figure 2.5: Three main pathways by which stressful life events influence human health and well-being (Schwarzer & Schulz, 2002) ...... 45 Figure 2.6: Transaction model of stress and coping (Lazarus, 1984) ...... 45 Figure 2.7: Study theoretical framework (adapted from Lazarus’s transaction model of stress and coping, 1984, and Schwarzer & Schulz’s conceptual model, 2002) ...... 47 Figure 3.1: Procedure to develop and validate the Vietnamese version of the study instruments ...... 61 Figure 3.2: Procedure to manage missing data (Howell, 2012) ...... 68 Figure 5.1: Outline of sampling procedure in Vietnam ...... 82 Figure 6.1: Preliminary study framework about the influences of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam...... 102 Figure 6.2: Final hypothesised model about the influences of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam...... 106 Figure 6.3: Final model of the influences of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam with standardized estimates (n=440)...... 108 Figure 6.4: Buffering role of social support on the influences of SLEs on health among older women in Vietnam with standardized estimates (n=440)...... 109 Figure 8.1: Preliminary study framework about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and in Australia ...... 130 Figure 8.2: Final hypothesised model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam...... 132 Figure 8.3: Final model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam with standardised estimates (n=440) ...... 134 Figure 8.4: The final hypothesised model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Australia ...... 137 Figure 8.5: Final model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Australia with standardized estimates (n=184) ...... 139
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List of Tables
Table 2.1: Brief facts about Australia and Vietnam ...... 18 Table 2.2: Percentage of population aged 65 and above in Australia and in Vietnam during 1950-2050 (United Nations, 2011) ...... 18 Table 2.3: Chronic disease profiles in Vietnam and Australia ...... 28 Table 2.4: Modifiable lifestyle risk factors for chronic diseases in Australian and Vietnamese people ...... 34 Table 3.1: Summary information about study instruments ...... 53 Table 4.1: Descriptive characteristics of the participants in Study 1 at two time points ...... 73 Table 4.2: Internal consistency reliabilities of the Vietnamese versions of the instruments in comparison with the internal consistency values of the instruments found in previous studies ...... 76 Table 4.3: Test-retest reliabilities of the translated instruments in comparison with the test- retest reliability values of the instruments found in previous studies...... 77 Table 6.1: Socio-demographic characteristics of the Vietnamese older women (n=440)...... 87 Table 6.2: Stressful life events reported by Vietnamese older women (n=440) ...... 89 Table 6.3: Perceived stress reported by Vietnamese older women (n=440) ...... 94 Table 6.4: Social support reported by Vietnamese older women (n=440) ...... 96 Table 6.5: Modifiable lifestyle characteristics of older women in Vietnam (n=440) ...... 98 Table 6.6: Depressive symptoms, health-related quality of life, and chronic disease reported by Vietnamese older women (n=440) ...... 100 Table 6.7: Correlation matrix among variables in Vietnamese dataset ...... 104 Table 7.1: Outline of current research in conjunction with the HOW study ...... 114 Table 7.2: Summary of data analysis plan ...... 118 Table 8.1: Socio-demographic characteristics of older women in Vietnam (n=440) and Australia (n=184) ...... 121 Table 8.2: Stressful life events among older women in Vietnam (n=440) and Australia (n=184) .....122 Table 8.3: Modifiable lifestyle characteristics among older women in Vietnam (n=440) and Australia (n=184) ...... 125 Table 8.4: Depressive symptoms, HRQOL, and chronic disease among older women in Vietnam (n=440) and Australia (n=184) ...... 127 Table 8.5: Correlation matrix among variables in Australian dataset (n=184) ...... 136
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List of Abbreviations
ADF: Asymptotic Distribution Free estimator
Adjusted GFI: Adjusted Goodness of Fit Index
AMOS: Analysis of Moment Structures
ANOVA: Analysis of Variance
BMI: Body Mass Index
CES-D: The Centre of Epidemiologic Studies Depression Scale
CVDs: Cardiovascular diseases
GFI: Goodness of Fit Index
GSDS: General Sleep Disturbance Scale
HOW: Healthy Ageing of Women
HRQOL: Health-related quality of life
LSC-r: Life Stressors Checklist (revised)
MAR: missing at random
MNAR: missing not at random
MCAR: missing completely at random
MCS: Mental health component scores
PCLOSE: p of Close Fit
PCS: Physical health component scores
QOL: Quality of life
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RMSEA: Root Mean Square Error of Approximation
SEM: Structural Equation Modelling
SF-12: Short Form 12 items
SLEs: Stressful life events
SRMR: Standardised Root Mean Square Residual
SPSS: Statistical Package for Social Sciences
T2DM: Type 2 diabetes
WHO: World Health Organisation
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Statement of Original Authorship
The work contained in this thesis has not been previously submitted to meet requirements for an award at this or any other higher education institution. To the best of my knowledge and belief, the thesis contains no material previously published or written by another person except where due reference is made.
Signature QUT Verified Signature
Date: March 2017
xv
Acknowledgements
I would like to send my first gratitude to my parents for their endless love, and the best support for my study. Their happiness in my achievements has given me strength to move forward. I also much appreciated my own small family for their understanding and companionship during my research journey.
Next, I would like to express my grateful appreciation to Professor Vo Tan Son for his belief in my success, Professor Debra Anderson, and Professor Anne Chang for their nominations of me to the QUT Postgraduate Awards. I feel fortunate to have gained the scholarship and conducted this PhD research. The journey has provided me many valuable life experiences, including chances to meet and learn from the most inspirational people ever in my life.
I specially would like to express my deepest gratitude to my brilliant supervision team (Professor Helen Edwards, Dr. Charrlotte Seib, and Professor
Debra Anderson). They not only kept providing me with timely knowledgeable guidance, they also cared for and supported me as needed. My mind was opened; my heart was warmed within their supervision.
I received great contributions from the translation team (Ms. Oanh, Ms.
Phuong, Ms. My Linh and Ms. Cuc) and from the expert panel (Dr. Phung, Dr. Ha and Dr. Bang) for the development of the Vietnamese versions of the research instruments. I also gained prompt support from the leaders of Elderly Unions in Tay
Thanh, Tan Phu, Ho Chi Minh City and in Tan Khanh Dong, Sa Dec, Dong Thap for participant recruitment and data collection. The tireless assistance from the research team (Ms. Tran, Ms. Phuong, Ms. Am, Ms. Hoang) for data collection and data
xvi
entry, and professional support from QUT staff (Dr. Martin Reese, Ms. Alina
Sarosike and Peter Sondergeld) are unforgettable for me. My research would not be successful without these all people, and I would like to send my sincerest thanks to them.
I am in debt to my participants for their valuable time and data. I would like to dedicate my research findings to improving health care for older women in the future.
This research received professional editing from Michelle Dicinoski following the university-endorsed guidelines and the Australian standards for editing research theses.
xvii
Chapter 1: Introduction
This research is about stressful life events (SLEs), modifiable lifestyle factors, depressive symptoms, health-related quality of life (HRQOL), and chronic disease among older women in Vietnam and Australia. To begin with, Chapter 1 introduces the study’s background, the research aims, objectives, questions and scope. Next, the chapter discusses the significance of the study. Then, the definitions of the study variables are described. Finally, the chapter presents the structural layout of the thesis.
1.1 BACKGROUND
In many parts of the world, the proportion of older people in the general population has also increased as life expectancy has increased (United Nations,
2011). The world population of people aged 60 and over is currently around 765 million, comprising 12% of the global population (United Nations, 2012). It is also estimated that by 2050, this number will increase to 20% globally (United Nations,
2011).
Despite innovations in health science, ageing is still a challenge for the healthcare system and society. Ageing is associated with decreased HRQOL (Le,
Nguyen, & Lindholm, 2010; Nilsson, Rana, Luong, Winblad, & Kabir, 2011). Older people usually report a lower HRQOL than those in younger groups (Le et al., 2010;
Nilsson et al., 2011). Ageing is also linked to higher prevalence of some chronic disease (Meyer et al., 2006). To be specific, a recent health survey in Australia showed that 70% of people aged 85 years and above had arthritis compared with
Chapter 1:Introduction 1
about 10% of people in the general population; 12.8% of people aged 65–74 had
T2DM compared with 5% for those aged 45–54; and 15% of people aged 70 years and over had coronary heart disease compared with 2.2% of those aged 25–69
(Australian Bureau of Statistics, 2012). Thus, concerns should be placed on healthcare for older people.
Among the older population, healthcare for women needs extra investment for a number of reasons. First, women comprise a higher proportion than men, with about 64% of the population, globally, aged 80 and over being female (United
Nations, 2011). Second, compared to men, women are also more vulnerable to experiencing psychosocial stress (Brown, Yelland, Sutherland, Baghurst, &
Robinson, 2011; Slopen, Williams, Fitzmaurice, & Gilman, 2011), have different modifiable lifestyle factors, lower HRQOL (Cruz, Lai, Goodrich, & Kilbourne, 2013;
Duenas, Ramirez, Arana, & Failde, 2011), and higher prevalence of several chronic conditions (Orfila et al., 2006). Third, currently, limited studies have investigated stress, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease from a gender perspective. Therefore, more research about stress, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women was warranted.
Theories about stress and health suggest that exposure to SLEs can increase health-compromising behaviours such as poor diet (Mainous et al., 2010), smoking
(Krueger, Saint Onge, & Chang, 2011; Mainous et al., 2010), excess alcohol consumption (Krueger et al., 2011; Slopen et al., 2011), physical inactivity (Krueger et al., 2011; Mainous et al., 2010), sleep disturbance (Ware, Kosinski, & Keller,
1996), and excess BMI (Barry & Petry, 2008). These unhealthy lifestyle behaviours
Chapter 1:Introduction 2
in turn, can decrease HRQOL (Kumarapeli, Seneviratne, & Wijeyaratne, 2011; Lau,
2013; Renzaho et al., 2013; Staniute, Brozaitiene, & Bunevicius, 2013; Takei et al.,
2012), and increase risk of chronic disease (Pyykkönen et al., 2010; Renzaho et al.,
2013; Thoits, 2010). In addition, exposure to SLEs can also increase depressive symptoms (Lee, Joo, & Choi, 2013; Renzaho et al., 2013; Slopen et al., 2011), which, in turn, contributes to reduced mental and physical health (Pittman,
Goldsmith, Lemmer, Kilmer, & Baker, 2012). The theory also indicated that perceived stress could be a mediator of the impact of SLEs on health (Lee et al.,
2013) while social support could buffer the impact of SLEs on health (Lazarus, 1966,
1984, 1990). However, the patterns by which SLEs influence health have been investigated to only a limited extent, and few studies have been conducted from a gender perspective. In addition, the majority of previous studies have used binary analysis, simple regression analysis or multiple regression analysis for data analysis.
This has limited investigation to solely examining direct influences among variables and has missed the opportunity to explore the indirect impact of SLEs. A combination of these direct and indirect influences among variables for a comprehensive model might increase statistical robustness. So, a more comprehensive investigation of stress, social support, modifiable lifestyle, HRQOL and chronic disease among older women in different cultures was required.
In Vietnam, the proportion of older people was 6.3% in 2011, and was projected to be 20% in a few decades (United Nations, 2011). There were 4.927 million women aged 60 and over, making up 58.3% of the population aged 60 and over (United Nations, 2011). Older women in Vietnam have a number of differences in life experiences. First, gender roles in this culture have caused discrimination. For example, girls have not generally received equivalent training to boys and
Chapter 1:Introduction 3
consequently have had less chance for paid employment (Bui et al., 2012). In addition, older Vietnamese women were taught “to obey their father when they are young, obey their husbands when they get married, and obey their sons when their husbands pass away” (Phan, 2001). In family life, Vietnamese women are expected to be home builders (đàn bà xây tổ ấm) (Phan, 2001). This means they do housework, take care of other family members, and keep the resilience for the whole family. In many instances, violence against wives has been considered to be acceptable (Krause, Gordon-Roberts, VanderEnde, Schuler, & Yount, 2015;
Marignoni, 2001; Rydstrom, 2003). Social norms inhibited women from divorce
(Vu, Schuler, Hoang, & Quach, 2014). Second, Vietnamese older women have also gone through war and life after war with limited resources (Merli, 2000; Witter,
1996). Third, Vietnam has recently gone through rapid socio-economic change, and this has been accompanied by an increase in the reporting of domestic violence
(Nguyen-Dang, Ostergren, & Krantz, 2008). Living in this context, Vietnamese older women may have stress related to many SLEs (Fisher et al., 2013; Nguyen-
Dang, Ostergren, & Krantz, 2009). Yet, knowledge about SLEs among Vietnamese older women was still largely unknown. Knowledge about perceived stress, social support, modifiable lifestyle, depressive symptoms, HRQOL and chronic disease among older women in Vietnam is also limited. To date, it appears that no study has been done on Vietnamese older women to investigate the impact of SLEs and perceived stress on modifiable lifestyle, depressive symptoms, HRQOL and chronic disease, social support and its roles in the impact of SLEs on perceived stress, depressive symptoms and mental health. Therefore, an investigation was needed for older women in Vietnam.
Chapter 1:Introduction 4
Cross-cultural comparison studies can be useful for consideration of future health interventions with people in different cultures. The existing comparisons of
HRQOL and chronic disease across nations show people in different countries or from different ethnic groups might have different experiences of health (Boyer et al.,
2012; Fu, Anderson, Courtney, & Hu, 2007; Fu, Anderson, Courtney, & McAvan,
2006; Ina et al., 2011; Kim & Sok, 2010; Koochek, Montazeri, Johansson, &
Sundquist, 2007; Nilsson et al., 2011; Skarupski et al., 2007; Wada et al., 2005), and of the pathways in which lifestyle influences health (Anderson. & Yoshizawa, 2007;
Luncheon & Zack, 2011; Nilsson et al., 2011). However, comparisons that do not use the same measurements are likely to limit the validity of findings.
In recent decades, the amount of research concerning Australian women’s
HRQOL and chronic conditions has increased (Emmanuel & Sun, 2013; Foottit &
Anderson, 2012; Renzaho et al., 2013). In contrast, a small amount of research has been conducted in this area on Vietnamese older people (Huong, Ha, Chi, Hill, &
Walton, 2012; Le et al., 2010; Nilsson et al., 2011; Wada et al., 2005), with none of these studies considering SLEs or women’s health perspectives. Better understanding about SLEs and their influences on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam in comparison to Australian women would be useful for modifying the Australian interventions to promote health for older women in Vietnam in the future. To date, to my knowledge, no cross-cultural comparison has been conducted on older women in
Vietnam and in Australia in terms of SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease and this knowledge was largely unknown.
Therefore, it is timely to conduct a study of older women in Vietnam and Australia to better understand SLEs, modifiable lifestyle factors, HRQOL and chronic disease.
Chapter 1:Introduction 5
This research used the same measurement instruments to fill the mentioned research gaps.
1.2 RESEARCH AIM AND OBJECTIVES
1.2.1 Overall aim
The aim of this research was to better understand SLEs, lifestyle and health among older women in Vietnam in relation to a similar cohort of Australian women.
The research also aimed to explore perceived stress and social support and their roles in the relationship between SLEs and health among older women in Vietnam.
Knowledge gained from this research could be used for consideration of modifying
Australian interventions to promote health for older women in Vietnam in the future.
1.2.2 Specific objectives To be specific, the research aimed to:
• Translate the research instruments into Vietnamese, and assess the translation equivalence, face validity, internal consistency reliability, and test-retest correlation reliability of the Vietnamese versions of the research instruments among older women in Vietnam.
• Describe SLEs, modifiable lifestyle factors (vegetable and fruit consumption, smoking, alcohol and caffeine drinking, physical activity, exercise, sleep problems, and BMI), depressive symptoms, HRQOL, and chronic disease among older women in Vietnam.
• Explore the influence of SLEs on modifiable lifestyle, depressive symptoms,
HRQOL, and chronic disease among older women in Vietnam.
Chapter 1:Introduction 6
• Examine perceived stress, social support, and their roles on the relationship between SLEs and health among older women in Vietnam.
• Examine similarities and differences in SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and those in Australia.
• Compare the model of the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam to that of similar women in Australia.
1.3 RESEARCH QUESTIONS
The research questions addressed in this research were:
• Do the Vietnamese versions of the study instruments have the equivalent meaning to their English versions, and achieve acceptable face validity, internal consistency and test-retest reliabilities among older women in Vietnam?
• What are the SLEs, their reported impact, characteristics of modifiable lifestyle factors, prevalence of those reporting symptoms of depression, HRQOL, and the number and prevalence of chronic disease reported by older women in Vietnam?
• How and to what extent are the SLEs associated with modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in
Vietnam?
• What are the levels of perceived stress and social support reported by older women in Vietnam?
• To what extent perceived stress mediates the influence of SLEs on health among older women in Vietnam?
Chapter 1:Introduction 7
• To what extent does social support buffer the influence of SLEs on perceived stress, depressive symptoms, and mental health among older women in Vietnam?
• What similarities and differences occur in SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease reported by older women in
Vietnam and those in Australia?
• What similarities and differences occur in modelling the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam and Australia?
1.4 SCOPE OF THE RESEARCH
The above research questions were addressed in three studies: (1) a pilot study for assessment of the translation equivalence and psychometric properties of the
Vietnamese versions of the research instruments; (2) an exploration of SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms,
HRQOL, and the number of chronic diseases among older women in Vietnam; and
(3) cross-cultural comparisons of SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and the number of chronic diseases among older women in
Vietnam and in Australia. In detail:
Study 1 involved translating a questionnaire from English to Vietnamese to gather data on SLEs, perceived stress, social support, modifiable lifestyle factors,
HRQOL and chronic disease, examining the translation equivalence, face validity, and testing the internal consistency reliabilities and test-retest reliabilities at a month long interval of the Vietnamese versions of the instruments among older women in
Vietnam (n=33).
Chapter 1:Introduction 8
Study 2 described SLEs, social support, perceived stress, modifiable lifestyle factors, HRQOL, and the number and prevalence of chronic disease among older women in Vietnam (n=440). The study also explored the influence of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. Further, the study examined the potential roles of social support and perceived stress on the relationship between SLEs and health among older women in Vietnam.
Study 3 included a cross-cultural comparison of SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in
Vietnam and Australia. This study also compared models describing the influence of
SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and Australia. In Australia, a secondary data analysis was performed on a cross-sectional dataset for the year 2012 from the longitudinal study Healthy Ageing of Women’s (HOW) (CI Anderson and CI Seib), which was derived with permission (n=184) (see Appendix C).
1.5 SIGNIFICANCE OF THE STUDY
This research has provided comprehensive descriptions about SLE, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam for the first time. The study also tested the model describing the direct and indirect influence of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease. In addition, the research explored the social support, perceived stress and their roles in the relationship between SLEs and health. Finally, the research compared SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease
Chapter 1:Introduction 9
among older women in Vietnam and in Australia and tested the model describing the direct and indirect influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease on data from older women in both nations.
This research is significant because knowledge gained from this research will be used to modify Australian interventions to promote health for older women in
Vietnam in the future. Findings from this research also has a number of practical applications, including consideration for resources, services, and policies for older women to manage stress, modify their lifestyle, improve HRQOL, and manage their chronic diseases. This will not only have the potential to provide Vietnamese older women with more fruitful and valuable years by maximising their HRQOL and reducing their risk of developing chronic disease, but also contribute significantly to the social and economic goals of the country. The implications gained from this research can also be useful for other Asian and Western countries that have similar characteristics to the study research populations.
1.6 DEFINITIONS OF VARIABLES
The following definitions were used for the studies reported in this thesis.
Stressful life events: events in one’s life which are usually frightening, upsetting or stressful to most people (Humphreys. et al., 2011).
Perceived stress: a subjective perception when one faces an event and appraises the event as out of his/her capacity to adapt (Lazarus, 1990).
Modifiable lifestyle factors: the ways in which women live that consequentially influence their health, including vegetable and fruit consumption,
Chapter 1:Introduction 10
smoking, alcohol and caffeine drinking, physical activity, exercise, sleep problems, and BMI (Australian Bureau of Statistics, 2014).
Social support: any support that a woman receives from friends or relatives
(Sherbourne & Stewart, 1991).
Chronic disease: health problems that last at least six months and generally progress slowly (World Health Organization, 2013d). In this study they include hypertension, coronary heart disease, stroke, T2DM, breast cancer, arthritis, osteoporosis, and depression (Murray et al., 2012).
Hypertension: a chronic condition in which the blood pressure is more than
140/90 mmHg without anti-hypertension medication (Australian Bureau of Statistics,
2014).
Coronary heart disease (also called ischaemic heart disease): a chronic condition of the blood vessels supplying the heart muscle (Australian Bureau of
Statistics, 2014).
Stroke: a chronic condition which occurs when the blood supply to part of the brain is interrupted or severely reduced, depriving brain tissue of oxygen and nutrients (Australian Bureau of Statistics, 2014).
Type 2 diabetes (T2DM): a chronic disease where insulin is no longer produced or not produced in sufficiently by the body(Australian Bureau of Statistics,
2014).
Breast cancer: a chronic disease in which the breast's cells grow and spread uncontrollly (Australian Bureau of Statistics, 2014).
Chapter 1:Introduction 11
Arthritis: a chronic condition in which joints become inflamed, causing pain, stiffness, disability and deformity (Australian Bureau of Statistics, 2014).
Osteoporosis: a chronic condition in which bone becomes thin and weak due to lack of calcium and leads to increasing risk for broken bones (Australian Bureau of
Statistics, 2014).
Depressive symptoms: a mental disorder characterised by sadness, and/or loss of interest in activities (L. S. Radloff, 1977).
Health related quality of life: an evaluation of the attributes of someone’s life when their health is concerned that includes perceived physical health and mental health (King & Hinds, 2012).
1.7 THESIS STRUCTURE
This research aimed to provide a comprehensive description of stress, social support, modifiable life style factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. The research also examined the influence of stress on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. The research further explored the potential roles of perceived stress and social support in the relationship between SLEs and health data of Vietnamese older women. Finally, the research compared findings of
SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease from Vietnamese older women with those among older women in Australia.
This thesis has nine chapters.
Chapter 1 provides a description of the study background, followed by research objectives, questions, scope, and the significance of the research. This chapter also
Chapter 1:Introduction 12
clarifies the definitions of variables in the studies and lays out the structure of the thesis.
Chapter 2 reviews the literature related to the study area. The chapter has seven sections. The first section provides a general overview of older women in Vietnam and Australia. This is followed by a discussion of some specific health issues related to ageing and gender. The third section discusses the concept of HRQOL and reviews HRQOL, chronic disease and their determinants. Section 4 discusses psychosocial stress, the influences of stress on health, and the pathways by which stressful life events can influence health. This section also reviews the potential role of social support and perceived stress on the influence of SLEs and health. Section 5 briefly explains the study’s theoretical framework. This chapter also provides information about ethical issues as well as the health and safety considerations in this research. The final section summarises the literature review about the research scope.
Chapter 3 presents methods used for Study 1, including study setting, design, sample, sampling methods, data collection, management and analysis. As there were no valid Vietnamese instruments to measure study variables, a detailed process for developing Vietnamese versions of the instruments and examining the psychometric properties of these Vietnamese versions of the instruments was also included in this chapter.
Chapter 4 presents the findings of Study 1 (n=33). This chapter has three sections. Section 1 presents the findings on the translation equivalence and face validity of the questionnaire for the study participants. Section 2 presents the findings on internal consistency and test-retest reliabilities of the Vietnamese version of the
Chapter 1:Introduction 13
instruments. Finally, Section 3 summarises the findings of Study 1 and explains how
Study 1 informed Study 2.
Chapter 5 presents the study methods of Study 2. This chapter has three sections. Section 1 presents the study design, setting, sample and sampling methods; and Section 2 presents the study instruments, data collection, management and analysis. The final section summarises the research methods used in Study 2 and provides a link to Chapter 6.
Chapter 6 presents the results of Study 2 regarding SLEs, social support, perceived stress, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam. This chapter has three sections.
Section 1 describes the SLEs, perceived stress, social support, modifiable lifestyle factors, HRQOL, and chronic disease among older women in Vietnam. Section 2 presents the pathways by which psychosocial stress influences modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in
Vietnam. Section 2 also describes the roles of perceived stress and social support in the relationship between SLEs and health. Finally, Section 3 summarises the findings of Study 2 and provides a link to Study 3.
Chapter 7 presents the study methods of Study 3. The chapter also provides information about HOW4 and the relationship of the current research with the
HOW4 study. Then, the research data analysis plan for Study 3 is described. Finally, the Chapter summarises methods used in study 3 and provides a link to Chapter 8.
Chapter 8 has six sections presenting the results of Study 3. The chapter presents comparisons of the SLEs, modifiable lifestyle factors, depressive symptoms,
HRQOL and chronic disease among older women in Vietnam and those in Australia.
Chapter 1:Introduction 14
This chapter also presents comparisons of the results of older women in Vietnam and older women in Australia regarding the influence of the SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease. Finally, this chapter summarises the findings of Study 3.
Chapter 9 presents a discussion and conclusion of the research findings. The discussion commences with a summary of the findings and then a discussion of the research findings in relation to past research. The chapter has seven sections. First is a description of the Vietnamese versions of the research instruments. Second is a discussion about the SLEs, modifiable lifestyle factors, depressive symptoms,
HRQOL, the number and prevalence of chronic disease among older women in
Vietnam and those in Australia. Third is a discussion about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic diseases among older women in Vietnam and Australia. Fourth, the chapter discusses perceived stress, social support, and their mediation roles in the relationship between
SLEs and health among Vietnamese older women. Fifth, the chapter discusses the strengths and limitations of this research. Sixth, it discusses the implications and recommendations generated from this research for healthcare practice, policy and future research. Finally, the chapter presents the conclusions of the research.
Chapter 1:Introduction 15
Chapter 2: Literature Review
Chapter 2 reviews the literature related to the study area. This chapter has six sections. Section 1 presents a brief overview of older women in Vietnam and
Australia. Section 2 discusses some specific health issues associated with ageing and gender. Section 3 discusses health-related quality of life (HRQOL) and chronic disease and their determinants. Section 4 reviews SLEs and the influence of stress on health. This section also reviews the potential role of social support and perceived stress on the influence of SLEs and health. Section 5 briefly introduces the study’s theoretical framework. This chapter also provides information about ethical issues, as well as the health and safety considerations in this research. The final section provides a summary of the literature review about the research scope.
2.1 OVERVIEW OF VIETNAM AND AUSTRALIA
Vietnam is the eastern-most nation on the Indochina Peninsula, located in
South East Asia, bordered by China to the north, Laos to the northwest, Cambodia to the southwest and the East Sea to the East (Vietnamese Embassy Australia, 2013).
Vietnam has eight regions: Northwest; Northeast; Red River Delta, North Central
Coast; South Central Coast; Central Highland; Southeast; and the Mekong River
Delta, covering 58 provinces and 5 metropolitan cities with 54 different ethnic groups (Vietnamese Embassy Australia, 2013). In 1945, the North of Vietnam gained independence from the French and Japanese, while South Vietnam was still under control of the pro-French administration and then the pro-American administration
(Vietnamese Embassy Australia, 2013). In 1975, South Vietnam was liberated and
Chapter 2:Literature Review 16
the country was united as one (Vietnamese Embassy Australia, 2013). During the period from 1975 to 1986, Vietnam dealt with innumerable difficulties, such as the consequences of war, social evils, the mass flow of refugees, the war against the Pol
Pot government in Cambodia at the southwest border, the dispute at the northern border, the isolation and embargo from the United States and Western countries, and continual natural disasters (Vietnamese Embassy Australia, 2013). In the early
1980s, Vietnam experienced its most serious ever socio-economic crisis, with inflation rates up to 774.7% (Vietnamese Embassy Australia, 2013). In 1986,
Vietnam underwent significant economic reform and since then the economy in
Vietnam has grown rapidly at the rate of about 8% every year (Vietnamese Embassy
Australia, 2012).
Currently, Vietnam is a developing country, with the second fastest economic growth rate among countries in East Asia and the fastest in Southeast Asia with GDP of about USD$239 billion and GDP per capital of USD$1527 (International
Monetary Fund, 2014). Vietnam has the world’s thirteenth largest population, with more than 93 million people living in 332,689 km², an area less than half the size of
New South Wales. More than half of the population are female (United Nations,
2012). The life expectancy in Vietnam in 2011 was 75 years (World Health
Organization, 2013f) ). The older population in Vietnam has been increasing from
4.2% of the population in 1950 to 6.3% in 2010, and has been projected to rise to
20% of the population by 2050 (United Nations, 2011). Among people aged 60 and above, women comprised 58.3% of the Vietnamese populations (United Nations,
2011).
Chapter 2:Literature Review 17
Table 2.1: Brief facts about Australia and Vietnam
Australia Vietnam
Capital Canberra Ha Noi
Main language English Vietnamese
Surface area 7,692,024 km² 332,689 km²
General population 23,8 million (2015) 93,5 million (2017)
General female population 11.176 million (50.3%) 44.431 million (50.6%)
Population aged 60 and above 5.072 million (22.8%) 8.446 million (9.8%)
Female population aged 60 + 2.753 million (54.3%) 4.927 million (58.3%)
GDP per capita USD 54,717 (2016) USD 1527 (2017)
Life expectancy 79.5-84 years old(2013) 75 years old (2011)
Table 2.2: Percentage of population aged 65 and above in Australia and in Vietnam during 1950-2050 (United Nations, 2011)
Percentage of population aged 65 and above 1950 2000 2010 2025 2050
Vietnam (%) 4.0 4.9 6.3 9.8 20.0
Australia (%) 8.1 12.5 13.9 19.1 23.8
In comparison, Australia is the world's sixth largest country, lying between the Indian and Pacific oceans, neighboured by Indonesia, East Timor and Papua New
Guinea to the north; Solomon Islands, Vanuatu and New Caledonia to the northeast, and New Zealand to the southeast (Australian Government, 2013b). Australia has six states, namely New South Wales, Queensland, South Australia, Tasmania, Victoria, and Western Australia, and two territories, the Australian Capital Territory and the
Northern Territory (Australian Government, 2013b). Australia is a developed country with currently the twelfth largest economy and the fifth highest GDP in the world
Chapter 2:Literature Review 18
(USD 1339 billion). Australia has about 23 million people and the fourth highest life expectancy for men (79.5 years) and women (84.0 years) in the world (Australian
Government, 2013a).The older population in Australia has been increasing significantly with 8.1% of the population in 1950 to 13.9% in 2010 and it was projected to be 19.1% in 2025 (United Nations, 2011). The number of older women in Australia is 2.753 million, comprising 54.3% of the population aged 60 and over
(United Nations, 2011). Table 2.1 provides an overview of Vietnam and Australia.
Table 2.2 shows changes in the percentage of older populations in Vietnam and in
Australia over the last six decades.
2.2 HEALTH ISSUES ASSOCIATED WITH AGEING AND GENDER
Despite the innovations in health science, ageing is still a challenge for healthcare systems and society. Older people also commonly report a high prevalence of sleep problems, including more fragmented night time sleep (Ohayon,
Carskadon, Guilleminault, & Vitiello, 2004), waking after sleep onset (Blackwell et al., 2008) and less effective sleep (Blackwell et al., 2008) than those in younger age brackets. Indeed, a meta-analysis reported that total sleep time (n = 2009) generally decreased by around 10 minutes for every 10 years of age, while waking after sleep onset (n = 1012) consistently increased about 10 minutes per 10 years from 30 years of age (Ohayon et al., 2004).
Ageing is associated with decreased quality of life (Le et al., 2010; Nilsson et al., 2011) and higher rates of chronic disease (Meyer et al., 2006). Among older people globally, the most common chronic conditions include hypertension, coronary heart disease, stroke, T2DM, breast cancer, arthritis, osteoporosis, depression, chronic obstructive pulmonary disease, and liver disease (Murray et al., 2012). For
Chapter 2:Literature Review 19
older women, the leading chronic diseases are coronary heart disease, stroke, hypertension, T2DM, arthritis, osteoporosis and breast cancer, with 28% having breast cancer, and 63% of those aged 77–85 years having arthritis, and 11% of those aged 65-74 having osteoporosis (Meyer et al., 2006).
Women generally also report more sleep disturbance than men. Indeed, women report higher mean scores of waking after sleep onset (OR=0.86, p<0.01) (Ohayon et al., 2004), more insomnia (Zhang & Wing, 2006), poor sleep quality (Baker,
Wolfson, & Lee, 2009), and greater daytime sleepiness (Baker et al., 2009). Gender differences have been attributed to hormonal fluctuations (Joffe et al., 2011; Kravitz
& Joffe, 2011) during the menstrual cycle (Dzaja et al., 2005), pregnancy (Bei, Coo,
& Trinder, 2015; Nowakowski, Meers, & Heimbach, 2013), post-partum (Bei et al.,
2015), and during menopausal transition (Moline & Broch, 2013).
Compared to men, women, especially older women, have been found to be more vulnerable to psychosocial stress (Olff, Langeland, Draijer, & Gersons, 2007;
Sacco, Bucholz, & Harrington, 2013; Slopen et al., 2011; You & Conner, 2009). The
Australian Health Survey found that women (12.7%) are more likely to experience high or very high psychological distress than men (8.8%)(Australian Bureau of
Statistics, 2012). The difference in vulnerability may be attributed to genetic factors, biological factors, sex hormones, and sexism and violence against women (Kendall-
Tackett, 2005). One significant reason that should be taken into account to explain this issue is that women are more likely to live in undesirable conditions and poverty than are men (Kendall-Tackett, 2005). This is particularly true if the women are widowed, members of a minority ethnic group, poorly educated or have a disability
(Kendall-Tackett, 2005), as these factors increase their risk of economic
Chapter 2:Literature Review 20
disadvantage (financial insecurity, food and nutrition, work environment, water and sanitation), social disadvantage (literacy, education, caregiving, widowhood), political disadvantage (disenfranchisement, advocacy participation), and cultural disadvantage (attitudes to ageing, women’s self-esteem) (Kendall-Tackett, 2005).
These factors have made older women experience cumulative economic barriers and shortages of resources (Kendall-Tackett, 2005).
In addition, women usually experience worse HRQOL (Cruz et al., 2013;
Duenas et al., 2011; French, Fletcher, & Irwin, 2004; Kendel et al., 2011;
Kirchengast & Haslinger, 2008; Lev-Ran et al., 2012; Miller & Dishon, 2006;
Soares, Simoes, Ramos, Pratt, & Brownson, 2010). Even controlling for age, education, marital status, activities of daily living, and numbers of chronic diseases, older women have shown a lower score in HRQOL (Hsu, 2007). With increasing age, women would appear to have worse HRQOL (Bisegger, Cloetta, von Bisegger,
Abel, & Ravens-Sieberer, 2005).
Women also appear to be more likely to have coronary heart disease, arthritis
(Australian Bureau of Statistics, 2012), osteoarthritis (Australian Bureau of Statistics,
2012; Meyer et al., 2006), breast cancer (Australian Bureau of Statistics, 2012), and depression (Krystal, 2004). The Australian Health Survey (2011b) found that in
2011-12, the arthritis prevalence among women was higher than that in men (17.7% of the population compared with 11.8%). Older women were considerably more likely to have arthritis, with 59.9% of women at ages 75 years and above having arthritis compared to 42.3% of men (Australian Bureau of Statistics, 2012).
Osteoporosis was also more common among women than men, affecting 5.3% of women compared with 1.2% of men in the general population and 22.8% of women
Chapter 2:Literature Review 21
aged 65 and over and over compared with around 5% of men aged 65 years and over
(Australian Bureau of Statistics, 2012). In Vietnam, recent research found that older women also had higher prevalence of hypertension than men (Pham et al., 2012), with hypertension affecting 58.2% of women compared with 53.4% % of men aged
65 years and over (Pham et al., 2012).
2.3 HEALTH-RELATED QUALITY OF LIFE, CHRONIC DISEASE AND
THEIR DETERMINANTS
2.3.1 Health-related quality of life and its determinants
The concept of QOL has been used widely in both academic and daily life environments (Bakas et al., 2012). Even though everyone believes that they know what QOL means, in reality, different people define the concept differently, and to date, there has been no concise or consistent definition (Bond & Corner, 2004, pp. 1-
10). Literature shows that definitions of quality of life (QOL) can be classified into two groups: (1) expert definitions, and; (2) lay definitions (Bond & Corner, 2004, pp.
1-10). Expert definitions of QOL can be divided into four main types including a global definition, component definition, a focused definition, and a combination definition (Bond & Corner, 2004, pp. 1-10). In contrast, lay definitions of QOL can be defined variously based on people, time, place and context (Bond & Corner, 2004, pp. 1-10). Overall, lay people describe “quality of life” in relation to the following components: family (children); social contacts; health; mobility/ ability; material circumstances; activities; happiness; youthfulness; and living environment (Bond &
Corner, 2004, pp. 1-10).
Within gerontology, QOL is a key measure in promoting positive experiences in later life and successful ageing (Bond & Corner, 2004, pp. 1-10). Experts have
Chapter 2:Literature Review 22
indicated that QOL for older people should have eight domains, including subjective satisfaction, physical and social environmental factors, socio-economic factors, cultural factors, health status factors, personality factors and personal autonomy factors (Bond & Corner, 2004, pp. 1-10). Older people may define their QOL more broadly and it is often argued that a “quality of life” study should have concern for enjoyment of one’s home, the importance of the community, social capital, and having enough money to meet basic needs, to participate in society, to enjoy life and to retain one’s independence and control over life (Bowling et al., 2003).
Similar to the QOL concept, the HRQOL concept does not have a “golden standard” definition (King & Hinds, 2012). Generally, the literature has classified the HRQOL concept into two groups: definition at the individual level and definition at the population level. At the individual level, HRQOL may include perceived physical health, mental health, health risks and conditions, functional status, social support, and socioeconomic status (King & Hinds, 2012), while at the population level, HRQOL may include resources, conditions, policies, and practices that influence a population’s health perceptions and functional status (King & Hinds,
2012).
The experts usually measure HRQOL instead of QOL (Bond & Corner, 2004, pp. 1-10) as it is an evaluation of the attributes of someone’s life in relation to their perceptions when their health is concerned (King & Hinds, 2012). Even though older people also indicated that their family relationships, health of close persons, standard of living, and social activities, spiritual or religious life were the most important aspects for their QOL (Bowling et al., 2003), the majority of older people indicated that the most important aspect of their lives is their own health (Bowling et
Chapter 2:Literature Review 23
al., 2003). In addition, measuring HRQOL can better determine the burden of preventable disease, injuries, and disabilities and better examine the relationships between HRQOL, risk factors, morbidity, and mortality (King & Hinds, 2012).
Finally, analysis of HRQOL data can identify populations with poor perceived health, as well as orient the interventions to improve their situations and to limit the more serious consequences (King & Hinds, 2012). Thus, HRQOL instead of QOL is preferable to measure in the studies with older people.
Literature demonstrates that a number of factors can influence HRQOL, including socio-demographics (Le et al., 2010; Nilsson et al., 2011), modifiable lifestyle factors (Dale et al., 2013; Heesch, van Uffelen, van Gellecum, & Brown,
2012; Luncheon & Zack, 2011), and environmental factors (Anderson. &
Yoshizawa, 2007; Tsai, Chi, Lee, & Chou, 2004). More specifically, social demographic factors like ageing (Hawkes et al., 2013; Le et al., 2010; Nilsson et al.,
2011; Soares et al., 2010; Yi, Zhong, & Yao, 2014), unemployment (Barisin, Benjak,
& Vuletic, 2011; DSouza, Karkada, & Somayaji, 2013; Hawkes et al., 2013; Jiang &
Hesser, 2006; Miller & Dishon, 2006; Yi et al., 2014), low income (Im, Lee, & Lee,
2014; Jiang & Hesser, 2006; Tajvar, Arab, & Montazeri, 2008; Yi et al., 2014), low health status or chronic conditions (Barisin et al., 2011; Dale et al., 2013; Miller &
Dishon, 2006; Soares et al., 2010; Yi et al., 2014), low literacy or education levels
(DSouza et al., 2013; Nilsson et al., 2011; Soares et al., 2010; Tajvar et al., 2008; Yi et al., 2014), and being widowed or divorced (Ham, 2011) could be associated with lower scores in HRQOL. However, links between gender, marital status, education, and HRQOL appeared to be inconsistent across the populations (Fu et al., 2007; Fu et al., 2006; Ham, 2011; Mugisha, Kouyate, Gbangou, & Sauerborn, 2002; Nilsson et al., 2011). A cross-cultural study found that being illiterate was associated with
Chapter 2:Literature Review 24
lower scores of HRQOL among Bangladeshi older people but could not find this association among Vietnamese older people (Nilsson et al., 2011). Similarly, while
Ham (2011) found that widowed or divorced women had significantly lower scores of HRQOL than married women, Nilsson and his team (2011) found that marital status was not significantly associated with HRQOL. Regarding gender, while women reported lower HRQOL scores among Vietnamese and Bangladeshi older people (Nilsson et al., 2011), women reported higher HRQOL scores in Australian and Taiwanese populations than their male counterparts (Fu et al., 2006).
Modifiable lifestyle factors such as smoking status (Holahan et al., 2013; Jiang
& Hesser, 2006; Shields, Garner, & Wilkins, 2013), alcohol consumption (Okoro et al., 2004; Wen et al., 2012), physical activity levels (Abell, Hootman, Zack,
Moriarty, & Helmick, 2005; Dale et al., 2013; Gómez, Moreno, Gómez, Carvajal, &
Parra, 2013; Hawkes et al., 2013; Heesch et al., 2012; Herman, Hopman,
Vandenkerkhof, & Rosenberg, 2012), BMI (Dale et al., 2013; Huang, Frangakis, &
Wu, 2006; Soares et al., 2010), and sleep problems (Strine & Chapman, 2005) were also reported to be associated with HRQOL. Specifically, those who smoked persistently had lower HRQOL than who had never smoked (Holahan et al., 2013;
Laaksonen, Rahkonen, Martikainen, Karvonen, & Lahelma, 2006; Shields et al.,
2013; Strandberg et al., 2008). Yet, female former smokers after 10 years of cessation would have similar levels of HRQOL to those who have never smoked
(Shields et al., 2013). Those who binge drink frequently also had lower HRQOL than non-drinkers (Okoro et al., 2004; Wen et al., 2012). Similarly, low physical activity levels were found to negatively associate with physical and mental health scores of HRQOL (Abell et al., 2005; Gómez et al., 2013). Even with people with arthritis, research showed that increased physical activity levels would increase their
Chapter 2:Literature Review 25
HRQOL (Abell et al., 2005) and with the people aged in their 70s and 80s, increased walking still improved their HRQOL (Heesch et al., 2012). In addition, excess weight was associated with decreased physical health (Herman et al., 2012; Huang et al., 2006), even though there were discordant associations between excess BMI and mental health reported in previous studies with some studies showing no associations
(Yan et al., 2004), and others reporting negative correlations (Daviglus et al., 2003;
Herman et al., 2012) or positive correlations (Arterburn, McDonell, Hedrick, Diehr,
& Fihn, 2004; Li et al., 2004). On the other hand, research revealed that sleep problems were associated with impairment in HRQOL (Strine & Chapman, 2005).
Environmental factors, such as residential area, were reported as factors that might influence HRQOL (Anderson. & Yoshizawa, 2007; Tsai et al., 2004). Chen et al. (2003) found that those living in areas with more social economic disadvantage reported poorer HRQOL. In addition, Tsai et al. (2004) indicated that among urban, rural and remote island older people, the differences in HRQOL were also significant, with urban older people having the highest scores in almost all scales. In contrast, the remote island older people had greatest HRQOL on mental health scales and the rural older people, particularly women, had the poorest HRQOL (Tsai et al.,
2004). Anderson and her team (Anderson. & Yoshizawa, 2007) also supported this finding by showing that after controlling for potential confounders, there were still significant differences in HRQOL between Australian and Japanese women.
2.3.2 Chronic disease and its determinants
In 2010, chronic disease reportedly caused an estimated 36 million deaths worldwide, representing more than 63% of all global deaths and 33% of disability adjusted life years (Murray et al., 2012). Cardiovascular diseases (CVDs) caused an
Chapter 2:Literature Review 26
estimated 17.3 million people’s deaths, representing 30% of all global deaths in 2012
(World Health Organization, 2013c). Diabetes affected 347 million people worldwide in 2012 (World Health Organization, 2013e). Cancer accounted for about eight million deaths (around 13% of all deaths) in 2008 globally and was projected to account for more than 13 million deaths in 2030 (World Health Organization,
2013b).
Data about chronic disease profiles in Vietnam and Australia are presented in
Table 2.3. In Vietnam, chronic disease has been the major cause of morbidity and mortality in hospitals (Hoang, Ng, et al., 2008). Chronic diseases accounted for
72% of of deaths and were responsible for 66.3% of total disability adjusted life years in 2010 (Vietnam Ministry of Health and Health Partnership Group, 2014).
About 68% of hospital admissions in Vietnam were related to chronic disease
(Ministry of Health, 2003). In Vietnam, 66% of deaths resulted from chronic disease
(Minh, Huong, Giang, & Byass, 2009), and estimated costs related to chronic diseases were about US$20 million annually (Minh et al., 2009). Among Vietnamese people aged 25-74, 39% had at least one chronic disease (Minh, Huong, & Giang,
2008). Among the older population in Vietnam, 15.3% - 45.6% have been reported to have hypertension (Hoang, Dao, & Kim, 2008; Minh, Byass, Dao, Nguyen, & Wall,
2007; Pham et al., 2009); 50.7% of women aged 60 and over were reported to have hypertension (Pham et al., 2012); 11.9% of women with heart disease (Hoang, Dao, et al., 2008), 15% with diabetes (International Diabetes Federation, 2014), 33.9% with arthritis, 10.4% with osteoporosis, 39-43% women aged 60+ had arthritis or osteoporosis (Mwangi, Kulane, & Le, 2015), 1.2% of the older population had depression (Ministry of Health, 2003), and 0.4% of women had suffered a stroke
(Hoang, Ng, et al., 2008).
Chapter 2:Literature Review 27
Table 2.3: Chronic disease profiles in Vietnam and Australia
Australia Vietnam
Hypertension 10.2%/ entire population 23.3%-45.6%/ 60+ population
60%/ people 60+ 50.7%/ women 60+ years old
Coronary heart 2.2% 25-69 years 11.9%/ women 65-74 years old 1 disease 15%/ 70 years +
Stroke2 253,000 persons/ entire 200,000 new case/ year/ entire
populations (1.8%) populations
0.4% / women 65-74
T2DM 4.3%/ 45-54-year-old 5.0%/ 30-69 population
12.8%/ 65-74-year-old population
Breast cancer Cancer: 1.5%/ entire population 0.03%/ entire population
12.5%/ women aged 85+
Arthritis 14.8% / entire population 33.9%/ 60+ population
52.1%/ 75+ population
70%/ 85+ population
Osteoporosis 3.3% / entire population 10.4%/ 60+ women population
15-23% women aged 50+
Depression 9.7%/ entire population 1.2%/ 60+ population
1. Heart disease, 2 Stroke and other cerebrovascular diseases
There were about 28 in 100,000 Vietnamese women experiencing breast cancer
(Nguyen, Laohasiriwong, Stewart, Nguyen, & Coyte, 2013), and there were 200,000 new cases of stroke each year (Ministry of Health, 2003).
Chapter 2:Literature Review 28
In Australia, chronic disease has been estimated to account for nearly 70% of the total health expenses, more than 80% of the disease and injury burden and almost
50% of all deaths (Meyer et al., 2006). In 2009, an estimated 375,800 Australians had had a stroke at some time in their lives (Australian Bureau of Statistics, 2012). In
2010, in Australia, 116,580 new cases of cancer were diagnosed and 14,181 of these were breast cancer (Australian Bureau of Statistics, 2012). In 2011-2012, osteoporosis was diagnosed in 725,500 Australian people (Australian Bureau of
Statistics, 2012). Further, within Australia, it was estimated that 253,000 people had stroke and other cerebrovascular diseases, 1.5% (or about 326,600 persons) had cancer, and 4.0% of the population (or approximately 875,400 people) had some type of diabetes (Australian Bureau of Statistics, 2012). Also, 14.8% the population
(or # 3.3 million people) had arthritis and 3.3% (or around 726,000 people) had osteoporosis (Australian Bureau of Statistics, 2012). Among Australian adults, 32 % have hypertension (Australian Institute of Health and Welfare, 2011b) with up to
60% of people aged 60 and over having hypertension (Australian Institute of Health and Welfare, 2016).
Among those aged 65 and above, more than 80% have at least one chronic condition (Meyer et al., 2006). In 2011-12, 15% of people aged 70 years and over had coronary heart disease compared with 2.2% of those aged 25–69 (Australian
Bureau of Statistics, 2012); 1.8% of the Australian population had stroke, with 69% of them aged 65 or over (Australian Bureau of Statistics, 2012); 15% of people aged
65–74 had diabetes, with 85.3% of the cases being T2DM, compared with 5% for those aged 45–54 (Australian Bureau of Statistics, 2012). In 2010, in Australia, about
70% of the cases diagnosed with cancer were people aged 60 and over (Australian
Bureau of Statistics, 2012). One in every eight women aged 85 and over in Australia
Chapter 2:Literature Review 29
had breast cancer (Cancer Council Australia, 2010). Among Australian people, 70% of people aged 85 years and above and 52.1% of people aged 75 years and above had arthritis compared with about 10% of people in the general population; and 9.7% (or around two million people) had depression (Australian Bureau of Statistics, 2012).
In 2011-2012, 15-23% women aged 50+ have osteoporosis; 83% of those diagnosed with osteoporosis were aged 55 and over (Australian Bureau of Statistics, 2012).
The literature has demonstrated that factors influencing chronic disease risk can be: (1) socio-demographic factors (Hoy, Rao, Nhung, Marks, & Hoa, 2013), (2) modifiable lifestyle factors (Hoy et al., 2013; Mainous et al., 2010), and (3) environmental factors (Pyykkönen et al., 2010; Renzaho et al., 2013; Segerstrom &
O’Connor, 2012; Thoits, 2010). To be specific, age (Minh et al., 2008), gender, ethnic background, family history, and genetic makeup are associated with chronic disease (Hoy et al., 2013), as are smoking (Minh et al., 2007; Minh et al., 2008), excess alcohol use (Minh et al., 2008), physical inactivity, high BMI (Pham et al.,
2009), and poor diet (low fruit and vegetable intake, high consumption of salty foods or saturated fats)(Cohen, Janicki-Deverts, & Miller, 2007; Cohen et al., 2009; Hoy et al., 2013; Mainous et al., 2010; McGuire et al., 2009; Meyer et al., 2006), being overweight or obese, abdominal adiposity, high blood pressure, elevated blood glucose and cholesterol (Hoy et al., 2013) and sleep disturbance (Grandner, Jackson,
Pak, & Gehrman, 2012; Grandner & Perlis, 2013). Poor sleep has been linked with a range of health issues (Irwin, 2015), including memory difficulties (Walker &
Stickgold, 2005), cognitive decline (Stuart, 2014), increased obesity risk (Kubo et al.,
2011), impaired immune function (Bollinger et al., 2009), susceptibility to infectious and inflammatory diseases (Vgontzas, Fernandez-Mendoza, Liao, & Bixler, 2013), hypertension (Cappuccio, Cooper, D'Elia, Strazzullo, & Miller, 2011; Palagini et al.,
Chapter 2:Literature Review 30
2013; Wang, Xi, Liu, Zhang, & Fu, 2012), cardiovascular disease (Azevedo et al.,
2014; Cappuccio et al., 2011), diabetes (Cappuccio, D'Elia, Strazzullo, & Miller,
2010), cancer (Luo, Sands, Wactawski-Wende, Song, & Margolis, 2013; Parent, El-
Zein, Rousseau, Pintos, & Siemiatycki, 2012; Zhang et al., 2013), and depression
(Baglioni et al., 2011; Stuart, 2014).
Socio-economic characteristics can influence chronic diseases through access to nutrition, health information, and services (Vietnam Ministry of Health and Health
Partnership Group, 2014). In Vietnam, common risks for chronic diseases are inappropriate diet (for example: inadequate vegetables and fruits and excess processed meat and sugar-sweetened drinks), tobacco smoking, harmful use of alcohol and drugs, lack of physical activity (Minh et al., 2008; Vietnam Ministry of
Health and Health Partnership Group, 2014), and high blood pressure (Hoy et al.,
2013). A study conducted in 1906 adults aged 25-64 in Ho Chi Minh city, Vietnam showed that many Vietnamese people (56.2%) were inactive and the prevalence of inactive people was higher in the female population and increased with age and income (Trinh, Nguyen, Dibley, Phongsavan, & Bauman, 2008). Another study on
2500 Vietnamese adults aged 25-74 found that 39% of adults had at least a chronic condition, 0.7% of women were smoking, compared with 59% of men; 67% of men were drinking alcohol at risky levels compared with 3% of women. A survey of 1407
Vietnamese people age 20-60 found that the prevalence of overweight and obesity was 33.6% among women and 31.6% among men; these prevalence increased with age (Cuong, Dibley, Bowe, Hanh, & Loan, 2007). Among people aged 65-74, 0.9% of women were smoking, and 7.7% of women were current drinking 2 or more drinks per day (Hoang, Ng, et al., 2008).
Chapter 2:Literature Review 31
Data about chronic disease associated lifestyle risk factors in Australian and
Vietnamese people are presented in Table 2.4. Among Vietnamese people, consumption of fruits and vegetables is lower than recommended amounts (Bui et al.,
2016). They consume approximately 3 serves of vegetables and fruits daily (Bui et al., 2016). The proportion of those who eat less than five servings of fruits and vegetables each day is quite high, with 77.1% of those living in urban areas and
83.7% of those living in rural areas (Vietnam Ministry of Health and Health
Partnership Group, 2014). People tend to select increasingly less healthy foods such as instant noodles and sugar-sweetened beverages (Vietnam Ministry of Health and
Health Partnership Group, 2014). Average daily salt intake per capita amounted to
18-22 grams, 3-4 times higher than recommended levels while meat intake is higher than recommended levels and seafood intake is lower than recommended levels
(Vietnam Ministry of Health and Health Partnership Group, 2014).
The table shows that 50% do not consume enough fruit. The prevalence of physical inactivity among those aged 60+ was about 60% and about 74.7% people aged 65-74 were overweight or obese (Australian Institute of Health and Welfare,
2016). Table 2.40.2% to 6.0% of Vietnamese women smoke (Vietnamese Ministry of Health, 2006). In 2010, smoking prevalence among those aged 15 and older in
Vietnam was 47.4% in men and 1.4% among females (Bui et al., 2016; Vietnam
Ministry of Health and Health Partnership Group, 2014; World Health Organization,
2016a). Vietnam is among 15 countries that have the highest number of smokers in the world, with approximately 15.3 million adult smokers (Vietnam Ministry of
Health and Health Partnership Group, 2014). Prevalence of alcohol consumption among Vietnamese women was 1-2% with 0.6% being binge-drinkers (4 standard drinks any day last week) (Bui et al., 2016).
Chapter 2:Literature Review 32
The prevalence of alcohol drinking at risk varied from 0.3-5% (Vietnamese
Ministry of Health, 2006). About 52-88% reported nfollowing a recommended diet
(Vietnamese Ministry of Health, 2006). The prevalence of physical inactivity was
11.0%-41.0%, with 37%-65% doing no exercise (Vietnamese Ministry of Health,
2006). Physical activity levels among women in rural areas were higher than those of women living in urban areas (Bui et al., 2016). The proportion of people with regular exercise in 2013 was only 27.2% (Vietnam Ministry of Health and Health
Partnership Group, 2014). A survey shows that 34% of people do not participate in any physical activity (Vietnam Ministry of Health and Health Partnership Group,
2014). The main reasons for their limited exercise were: no time (84%), reluctant to get up early for exercise (9%), and lack of sport facilities and spaces (2%) (Vietnam
Ministry of Health and Health Partnership Group, 2014).
More than 13% to 31.2% Vietnamese women aged 65-74 are overweight and
1.3-2.6% are obese (Walls et al., 2009). On the other hand, among Australian adults,
12.8% are daily smokers, 13.8% never consume a full serve of alcohol, 20% have more than 2 drinks per day (Australian Institute of Health and Welfare, 2016), and
6%-8% of older women consume alcohol at risky levels (Australian Institute of
Health and Welfare, 2016). Most (92%) do not consume enough vegetables, and
50% do not consume enough fruit. The prevalence of physical inactivity among those aged 60+ was about 60% and about 74.7% people aged 65-74 were overweight or obese (Australian Institute of Health and Welfare, 2016).
Chapter 2:Literature Review 33
Table 2.4: Modifiable lifestyle risk factors for chronic diseases in Australian and Vietnamese people
Australia Vietnam
Smoking Smoke daily: 12.8% / 18+ Current smoker: 47.6%-68%/ population male; 0.2%-6.0%/ female
Alcohol 86.2% drinking Excessive drinking: Excessive drinking:
20%/ entire population 9.1-61%/ male and 0.3-5% /
6%-8%/ women female
Diet Consuming the recommended Consuming the recommended diet: 9.6%/ aged 65-74 diet: 59.4-87%/ male and 52%- population 88%/ female.
92% do not consume enough vegetables, 50% do not consume enough fruit
Physical Sedentary: 60%/ 60+ Inactivity: 15%-63% of male inactivity and population and 11%-41% of female exercise Low levels of exercise: 25.8% No exercise: 37%-65% 75 + population
Overweight, Overweight or obese: 63.4% / Overweight: 13-31.2% obesity 18+ population; 74.7% / aged Obesity: 1.3%-2.6% 65-74 years
Overweight: 35.0% / 18+ population
Obese: 28.3% / 18+ population
Apart from these above factors, environment pollution, food contamination, occupational diseases and accidents and stressful working environments are also
Chapter 2:Literature Review 34
contributing to increasing prevalence of chronic disease among Vietnamese people
(Vietnam Ministry of Health and Health Partnership Group, 2014).
2.4 PSYCHOSOCIAL STRESS AND HEALTH
2.4.1 Stress: definition and the impact on health
The definitions of stress vary in the literature. In general, these definitions can be categorised into three main types, including either internal or external stimulus- based (stressor), response-based (stressor-response), or transactional-based (stressor- appraisal, perceived stress) (Selye, 1983). Literature usually uses the term “stressor” to refer to objective events or experiences (Selye, 1956, 1983), while the term
“stress response” refers to the physiological responses following a demanding condition (Selye, 1956, 1983), and “stress appraisal” refers to a subjective state of arousal (Lazarus, 1966, 1984).
The stimulus-based literature defines stress as an objective event or experience that has a substantial demand and requires adaptation efforts (stressors) (Holmes &
Rahe, 1967). The response-based tradition defines stress as nonspecific physiological responses following a demanding condition (Selye, 1956, 1983). From the stimulus- based literature, it was found that the strength of the physiological responses can differ as some people may be more vulnerable to the stimuli (Stein, Schork, &
Gelernter, 2008). Based on this response-based tradition, Selye (Selye, 1956, 1983) indicated that there are three stages of stress: (1) alarm; (2) resistance, and; (3) exhaustion. Stage 1 begins when the body releases Adrenocorticotropic Hormone
(ACTH) and prepares for survival (fight or flight) while Stage 2 is characterised by a decrease in ACTH and the adaptation and mal-adaptation process that occurs in the body (Selye, 1956, 1983). Finally, Stage 3 happens when all energy for adaptation
Chapter 2:Literature Review 35
has been used, and evidence of physiological deterioration or dysfunction is seen
(Selye, 1956, 1983). The transactional-based tradition focuses on the subjective appraisal of one’s abilities and resources and one’s affective responses to events and experiences (Lazarus, 1966, 1984). Although there are several definitions of stress, the fact is that the common key element in all definitions is the presence of an event or experience which exceeds one’s capacity to adapt. To maximise the exploration of stress, this research measures both stressors and perceived stress when examining psychosocial stress. In terms of stressors, the study examined the exposure to SLEs.
In terms of perceived stress, the study examined the impact of SLEs in the previous year and perceived stress.
Stress is an important predictor for decreased HRQOL (DiSipio, Hayes,
Newman, & Janda, 2009; Lu et al., 2012; Staniute et al., 2013; Yi et al., 2014) including physical health and mental health aspects (Im et al., 2014; Lu et al., 2012), and a number of chronic conditions (Bergelt, Prescott, Grønbaek, Koch, & Johansen,
2006; Cosgrove, Sargeant, Caleyachetty, & Griffin, 2012; Kershaw et al., 2014;
Steptoe & Kivimaki, 2012; Sumner et al., 2015). In terms of physical health, it is found that stress increases risk of chronic disease, such as hypertension (Rosenthal &
Alter, 2012), coronary heart disease or cardiovascular diseases (Sumner et al., 2015), stroke (DeVries et al., 2001), cancer (Bergelt et al., 2006), and diabetes (Cosgrove et al., 2012). Regarding mental health, stress is found to lead to suicidal ideation, anxiety (Goenjian et al., 2000)and depression (Hammen, 2005; Risch, Herrell,
Lehner, & et al., 2009; Risch, Herrell, Lehner, Liang, et al., 2009).
Chapter 2:Literature Review 36
2.4.2 Mechanisms by which stressful life events influence health
Stressful life events (stressors) can happen at any point in someone’s life and might include accidents (Heim, Plotsky, & Nemeroff, 2004), surgery (Heim et al.,
2004), chronic illness (Heim et al., 2004), child maltreatment, dysfunctional relationships between parent and child (Heim et al., 2004), unstable families with inadequate parental care (Heim et al., 2004), parental loss (Heim et al., 2004), academic failure (Marmot, 2005), poverty (Heim et al., 2004; Marmot, 2005), natural disasters (Heim et al., 2004), or terrorism-related experiences and war (Heim et al.,
2004).
Stressors can be jobs with high demand, low control and low social support
(Alexander et al., 2007) or job loss (Marmot, 2005). Stressors can come from family or marital life, such as parenting (Alexander et al., 2007), caring for sick or elderly relatives (Alexander et al., 2007), illness or the death of a loved one (Alexander et al., 2007), intimate partner violence (Humphreys et al., 2012), and divorce
(Alexander et al., 2007). Stressors can also be major financial crises (Alexander et al., 2007), or political violence (Eisenman, Gelberg, Liu, & Shapiro, 2003).
Stressors can be classified into two groups: continuing stressors (or chronic stress) and new stressors (or acute stress). Continuing stressors, also called stressors from earlier developmental times, exist from an earlier point of life (Kendall-Tackett,
2005). An example of this type of stressor is that of having childhood abuse experiences or being a mother of a child with a chronic illness or disability (Kendall-
Tackett, 2005). New stressors are those that newly appear in a period of life
(Kendall-Tackett, 2005). For example, caregiving, loss of loved ones, role changes, and friendships (Kendall-Tackett, 2005). Stressful life events can influence human
Chapter 2:Literature Review 37
health and well-being through three pathways, including changing physiology, developing unhealthy lifestyle behaviours, and causing negative affective feelings
(Schwarzer & Schulz, 2002).
2.4.2.1 Stressful life events influence health through physiological changes
When the body is exposed to stressors, the cerebral cortex sends a message to the amygdala and hypothalamus (Alexander et al., 2007), leading to the release of the Adrenocorticotropic Hormone (ACTH), a hormone targeting the suprarenal gland
(Alexander et al., 2007). When the ACTH level increases, the adrenal cortex will secrete corticoids and aldosterol, the adrenal medulla will release catecholamine, adrenalin and noradrenalin (Juster, McEwen, & Lupien, 2010; McEwen, 2003).
Corticoids can increase the absorption of glucose in the intestine, reduce the use of glucose in the body, and create glucose from acid Amin and reabsorb of Na+
(Alexander et al., 2007). Adrenalin increases the heart rate, blood pressure, and decomposition of glycogens in the liver, and reduces glucose use, while noradrenalin can contract blood vessels (Alexander et al., 2007).
In addition, when experiencing stress, the sympathetic nervous system and the hypothalamic pituitary axis modulate the immune and non-immune cells to release cytokines (Wirtz et al., 2007). Then, the cytokines stimulate the pituitary gland and adrenal cortex to secrete cortisol and activate the non-adrenergic and serotonergic system (Dunn, Swiergiel, & de Beaurepaire, 2005), inhibit the hypothalamic pituitary axis action and contribute to “flight or fight” responses (Juster et al., 2010). These responses can be described as elevations of heart rate, respiratory rate, blood glucose, and blood pressure (Juster et al., 2010). When cumulative stress exceeds the body’s ability to recover from physiological changes to a homeostasis status, stress can lead
Chapter 2:Literature Review 38
to physiological deterioration or dysfunction (Browning, Cagney, & Iveniuk, 2012;
Repetti, Robles, & Reynolds, 2011), potentially contributing to poor health outcomes
(Schwarzer & Schulz, 2002). Figure 2.1 describes the pathway by which SLEs influence health through physiological changes.
Stressful life events Physiological changes Health
Figure 2.1: Relationships among stressful life events, physiological changes and health
2.4.2.2 Stressful life events influence health through unhealthy lifestyles
There is an increasing amount of evidence that stress exposure could result in poor diet (Mainous et al., 2010), smoking (Krueger et al., 2011; Mainous et al.,
2010), excess alcohol drinking (Krueger et al., 2011; Lipsky, Kernic, Qiu, & Hasin,
2015; Slopen et al., 2011), physical inactivity (Krueger et al., 2011; Mainous et al.,
2010), sleep disturbance (S.-Y. Lee & Hsu, 2012), and excess BMI (Barry & Petry,
2008). These lifestyles are associated with decreased HRQOL (Ham, 2011;
Kumarapeli et al., 2011; Lau, 2013; Lau & Yin, 2011; Renzaho et al., 2013; Staniute et al., 2013; Takei et al., 2012; Ward & Tanner, 2010), and increased risk of chronic disease (Pyykkönen et al., 2010; Renzaho et al., 2013; Segerstrom & O’Connor,
2012; Thoits, 2010). Specifically, those who smoked persistently had lower HRQOL than who has never smoked (Heikkinen, Jallinoja, Saarni, & Patja, 2008; Holahan et al., 2013; Laaksonen et al., 2006; Shields et al., 2013; Strandberg et al., 2008), and a long-term smoking cessation for better HRQOL with an evidence that former female smoker after 10 years of cessation would have similar level of HRQOL to those who have never smoked (Shields et al., 2013). Low physical activity level was found to be negatively associated with physical and mental health scores of HRQOL (Abell et
Chapter 2:Literature Review 39
al., 2005; Gómez et al., 2013; Herman et al., 2012). Even with people with arthritis, research showed that increased physical activity levels would increase their HRQOL
(Abell et al., 2005) or with the people aged 70s-80s, only increased walking still improved their HRQOL (Heesch et al., 2012). Sleep problems were associated with impairment in HRQOL (Strine & Chapman, 2005). Excess weight was associated with decreased physical health (Herman et al., 2012; Huang et al., 2006), HRQOL
(Hassan, Joshi, Madhavan, & Amonkar, 2003; Herman et al., 2012). Obesity was also found to be associated with chronic disease such as depression (Roberts,
Deleger, Strawbridge, & Kaplan, 2003). Exercise and healthy diet were correlated with increased HRQOL (Hassan et al., 2003). These association may be different for people from different cultures (Luncheon & Zack, 2011). Figure 2.2 describes the pathway by which SLEs influence health through unhealthy lifestyles.
Unhealthy eating Smoking Excess alcohol drinking Stressful life events Physical inactivity Health Sleep disturbance Excess BMI
Figure 2.2: Relationships among stressful life events, modifiable lifestyle factors, and health 2.4.2.3 Stressful life events influencing on health through negative affection
Numerous studies have found that people who experience SLEs have increased rates of depression (Kendler, Hettema, Butera, Gardner, & Prescott, 2003; Lee et al.,
2013; Phillips, Carroll, & Der, 2015; Renzaho et al., 2013; C. Seib et al., 2014;
Slopen et al., 2011). A cross-sectional study done on 1257 females found that, after adjusting for marital status, education, income, employment status, pregnancy status,
Chapter 2:Literature Review 40
or being abused as a child, those who experienced abuse in their adult intimate relationships would be more likely to experience depression than others (Hegarty,
Gunn, Chondros, & Small, 2004). In turn, depression significantly contributed to decreasing HRQOL (Arslan, Ayranci, Unsal, & Arslantas, 2009; Hawkes et al.,
2013; Pittman et al., 2012; Yi et al., 2014) and to the development of more health problems (Bajor et al., 2013). Yet, these associations may be different for people from different cultures (Luncheon & Zack, 2011). Figure 2.3 describes the pathway by which SLEs influence health through negative affective.
Stressful life events Depression Health
Figure 2.3: Relationships among stressful life events, depression and health
2.4.2.4 The roles of social support and perceived stress in the relationship between stressful life events and health
From a transactional-based perspective, Lazarus (1966, 1984) states that psychologically, people will experience stress when they deal with a situation in which their resources cannot meet the situational requirements and they will anticipate loss or harm. People may be less likely to appraise the stimuli as stressors or experience the stimuli as stressful than others when they have more available resources such as instrumental support, emotional support, and successful coping experiences (Lazarus, 1966, 1984; Lee & Hung, 2015; Lu et al., 2012). This suggests that social support could alleviate the impact of SLEs on perceived stress (Gray-
Stanley et al., 2010; Salgado, Castaneda, Talavera, & Lindsay, 2012).
Research also showed that social support not only had direct significant associations with HRQOL, (Årestedt, Saveman, Johansson, & Blomqvist, 2013;
Bekele et al., 2013; Eom et al., 2013; Filazoglu & Griva, 2008; Hawkes et al., 2013;
Chapter 2:Literature Review 41
Park et al., 2015; Staniute et al., 2013; Yi et al., 2014) and mental health (Ayers et al., 2009; Hou, Cerulli, Wittink, Caine, & Qiu, 2015), but also could protect against the negative effects of stress on health (Chen, Siu, Lu, Cooper, & Phillips, 2009;
Gray-Stanley et al., 2010; Mehnert, Lehmann, Graefen, Huland, & Koch, 2010;
Salgado et al., 2012; Staniute et al., 2013). To be specific, a recent study indicated that the more social support people had, the less negative effects of SLEs on health they would experience (Manuel, Martinson, Bledsoe-Mansori, & Bellamy, 2012;
Salgado et al., 2012), especially on mental health (Chen et al., 2009; Chojenta,
Loxton, & Lucke, 2012; Im et al., 2014; Wang, Lau, Chow, Thompson, & He, 2013).
Research also revealed that the influence of social support on health could be mediated by perceived stress (Zhou et al., 2010). In addition, by using structural equation modelling, a recent study revealed that perceived stress could mediate the relationship between SLEs and depression (Lee et al., 2013). These mean that: (1) when people are exposed to stressful life events, they are more likely to feel stressed when they find that they do not have adequate support to deal with the situation
(Lazarus, 1966, 1984, 1990); and (2) perceived stress can mediate the impact of stress, while social support can buffer the impact of stress on health (Chae, Park, &
Kang, 2014; Lee et al., 2013). Figure 2.4 describes roles of social support and perceived stress in the relationship between stressful life events and health.
SLEs Perceived stress Depression, health
Social support
Figure 2.4: Relationships among stressful life events, social support, perceived stress and health
Chapter 2:Literature Review 42
2.5 THE STUDY’S THEORETICAL FRAMEWORK
To find an appropriate framework for this study, both HRQOL models and stress models were examined. There are several existing HRQOL models in the literature (Bakas et al., 2012; A. Bowling, Bannister, Sutton, Evans, & Windsor,
2002; Ann Bowling & Gabriel, 2004), for example Wilson and Cleary’s HRQOL model (Wilson & Cleary, 1995), and Ferran and colleagues’ HRQOL model
(Ferrans, Zerwic, Wilbur, & Larson, 2005). A recent review suggested that Ferran and colleagues’ HRQOL model (Ferrans et al., 2005) and a recent revision of Wilson and Cleary’s HRQOL model (Wilson & Cleary, 1995) should be used to underpin the study investigation as these are two of the most commonly used models in
HRQOL research. Using these models allows the researcher to compare the study findings with current literature while “quality of life” still has no “golden” definition
(Bakas et al., 2012). In addition, Ferrans’ HRQOL model added individual and environmental factors into the model to explain quality of life, so that researchers can explore both internal and external factors influencing HRQOL and the relationships existing in the model can be tested and revised (Bakas et al., 2012).
Finally, using this most common model will promote a coherence across the literature of quality of life research and will allow the knowledge to advance more quickly (Bakas et al., 2012). However, this model does not provide a framework to explore the pathways by which psychosocial stress may influence health, including
HRQOL and chronic disease. Therefore, another model should be used in this study to examine these elements.
The current study used Schwarzer and Schulz’s conceptual model (see Figure
2.5) to investigate the associations among study variables. Schwarzer and Schulz
Chapter 2:Literature Review 43
(2002) suggested three main pathways of how SLEs influence human health and well-being. First, SLEs are linked to illness by changing the physiology, including the immune system, cardiovascular system, and endocrine reactivity, which causes illness (Schwarzer & Schulz, 2002). Another pathway suggests that people who experience SLEs will adopt an unhealthy lifestyle as a way to release their stress and this leads them to illness (Schwarzer & Schulz, 2002). Finally, stress is linked with constant rumination, worrying, anxiety, pessimism, depression, and anger
(Schwarzer & Schulz, 2002). Beside these three main pathways, Schwarzer and
Schulz (2002) also acknowledged that some factors may buffer the impact of stress on HRQOL and chronic illness, including social support, age, gender, personality, appraisals, coping, and genes.
The current study also integrated the Transaction Model of Stress and
Coping (Lazarus, 1984) (see Figure 2.6) into Schwarzer and Schulz’s conceptual model (Schwarzer & Schulz, 2002), and hypothesised that exposure to SLEs will develop or reinforce health-compromising behaviours such as smoking (Krueger et al., 2011; Mainous et al., 2010), excess alcohol and caffeine consumption, (Krueger et al., 2011; Slopen et al., 2011), poor diet (Mainous et al., 2010), physical inactivity
(Krueger et al., 2011; Mainous et al., 2010), sleep disturbance, and elevated BMI
(Barry & Petry, 2008). With these health-compromising behaviours, people will experience worse HRQOL (Kumarapeli et al., 2011; Lau, 2013; Renzaho et al., 2013;
Staniute et al., 2013; Takei et al., 2012), and become more likely to have chronic illness (Pyykkönen et al., 2010; Renzaho et al., 2013; Thoits, 2010).
Chapter 2:Literature Review 44
UNHEALTHY LIFESTYLE Unhealthy diet Smoking Excess alcohol consumption Sedentary lifestyle Sleep deprivation Elevated BMI
ILLNESS INDICATORS STRESSFUL PHYSIOLOGICAL CHANGES LIFE EVENT
NEGATIVE AFFECT Depressed mood
Figure 2.5: Three main pathways by which stressful life events influence human health and well-being (Schwarzer & Schulz, 2002)
Stressors Perceived stress Coping Health outcomes
Primary appraisal (Ex: social support) Reappraisal
Figure 2.6: Transaction model of stress and coping (Lazarus, 1984)
In addition, the study also hypothesised that people exposed to SLEs will be more likely to develop depression (Lee et al., 2013; Renzaho et al., 2013; Slopen et al., 2011) and this will lead them to decreased HRQOL (Pittman et al., 2012) and more chronic conditions, though social support could mediate the impact of SLEs and buffer its impacts on health (Gray-Stanley et al., 2010; J. I. Manuel, M. L.
Martinson, S. E. Bledsoe-Mansori, & J. L. Bellamy, 2012; Mehnert et al., 2010;
Salgado et al., 2012; Staniute et al., 2013) (See Figure 2.7).
Chapter 2:Literature Review 45
2.6 HEALTH AND SAFETY STATEMENT, AND ETHICAL APPROVALS
This research was granted ethical approvals from the Research Ethics
Committee of the University of Medicine and Pharmacy, Ho Chi Minh City,
Vietnam (Ethical clearance number: 192/DHYD-HD) and from the Human Research
Ethics Committee of Queensland University of Technology in 2014 (Ethical clearance number: 1400000256). Acceptance to conduct the study and to collect data was received from the community leaders of 16 rural and urban suburbs in Vietnam.
With regards to the secondary data analysis of the HOW4 study data, in which the supervision team were CIs (CI Anderson and CI Seib), this study was granted ethical approval in 2012 (Ethical clearance number: 1100000171) and further ethical approval was not required for this further data analysis
This study did not involve any use of biological, microbiological or biochemical material. The research did not work with high risk materials. Before data collection, the prospective participants received the study information papers and consent forms. The study information papers explained in plain language the research aims and the way participants would participate, and also contained a statement of confidentiality. The consent form asked the prospective participants to sign to show their agreement to participate in the study and the consent forms were kept separately from the completed surveys at all times.
A clear understanding of the information about the study and a signed consent form was obtained from each participant prior to data collection.
Participation in the research was voluntary and respondents’ consent was able to be withdrawn at any time.
Chapter 2:Literature Review 46
UNHEALTHY LIFESTYLE Low vegetable consumption HRQOL STRESSFUL LIFE EVENTS: Number of SLEs Low fruit consumption Decreased Reported impact of SLEs in previous year Smoking physical, and
Excess alcohol consumption mental health Insufficient physical activity
Sleep deprivation Elevated BMI
PHYSIOLOGICAL CHANGES
CHRONIC NEGATIVE AFFECT Depressed mood ILLNESS SOCIAL PERCEIVED SUPPORT STRESS
Figure 2.7: Study theoretical framework (adapted from Lazarus’s transaction model of stress and coping, 1984, and Schwarzer &
Schulz’s conceptual model, 2002)
Chapter 2:Literature Review 47
No personal identifiable information was noted on the questionnaire. All data were kept in the strictest confidence. The completed questionnaire was kept in an envelope and all of these envelopes were kept in a locked cabinet in a secure room.
Data were entered into Statistical Package for the Social Sciences (SPSS) 23.0. All electronic data were kept in a password-locked computer in a private and secure place. Only the researcher, data entry assistants and the supervisors could access the data with the key and identity card. Care was taken throughout the project that participants were clear with the language used. De-identifiable data were used. For the data analysis, no individual data were reported.
2.7 SUMMARY
Numerous studies have examined factors influencing HRQOL and chronic disease; however, less is known about the impact of SLEs on these health indicators among older women. Also, the patterns by which SLEs influence health have been investigated in a limited context. To my knowledge, no study has been done on
Vietnamese older women. Few studies were conducted from a gender perspective. In addition, the majority of previous studies used binary analysis, simple regression analysis or multiple regression analysis for data analysis and this limited their investigation to direct influences among variables but missed the indirect influence of SLEs. A combination of these direct influences among variables for a comprehensive model might increase the statistical errors. Therefore, a further comprehensive investigation of the direct and indirect influence of SLEs on health among older women across different cultures was warranted. Also, social support and perceived stress might mediate the influence of SLEs on health, so exploration of
Chapter 2:Literature Review 48
this mediation while investigating the influence of SLEs on health has the potential to yield a better description of the pathways by which SLEs influence health among older women. Moreover, while understanding the similarities and differences across the nations would benefit specific interventions in the future for particular populations, no comparison study on SLEs, lifestyle factors, HRQOL and chronic disease has been done on older women in Vietnam and Australia. Thus, it is warranted to conduct a cross-cultural comparison study on SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease and health among older women in Vietnam and Australia.
This study integrated The Transaction Model of Stress and Coping (Lazarus,
1984) and Schwarzer and Schulz’s conceptual model (Schwarzer & Schulz, 2002) to build a study framework to underpin the examination of relationships among SLEs, lifestyle factors and HRQOL chronic disease among older women in Vietnam and
Australia. The study hypothesised that psychosocial stress will develop or reinforce health compromising behaviours such as unhealthy diet, sedentary lifestyle, excess alcohol consumption, excess caffeine consumption, smoking, sleep deprivation, and elevated BMI. With these health-compromising behaviours, people will experience worse HRQOL as well as more chronic illness. In addition, it is also hypothesised that people with psychosocial stress will be more likely to develop depression and this will lead to decreased HRQOL and more chronic conditions. Finally, the study hypothesised that social support and perceived stress will mediate the impact of
SLEs on health. The research included three studies: (1) a pilot study, which assessed the translation equivalence, face validity, internal consistency reliability, and test retest reliability of the Vietnamese versions of the research instruments; (2) an exploration of stressful life events, perceived stress, social support, modifiable
Chapter 2:Literature Review 49
lifestyle factors, depressive symptoms, HRQOL, and the number of chronic diseases among older women in Vietnam; and (3) the cross-cultural comparisons of stressful life events, modifiable lifestyle factors, depressive symptoms, HRQOL, and the number of chronic diseases among older women in Vietnam and in Australia. The next chapter will present research methods for Study 1.
Chapter 2:Literature Review 50
Chapter 3: Research methods – Study 1
Study 1 translated a questionnaire from English to Vietnamese to gather data on demographic characteristics, SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. The study also examined whether the Vietnamese versions of the study instruments had the equivalent meaning to their English versions, determined the feasibility of the data collection procedure, and assessed whether the Vietnamese versions of the study instruments had acceptable face validity, internal consistency reliabilities, and test-retest reliabilities among a sample of older women in Vietnam.
This chapter presents methods used for Study 1. The chapter has six sections.
Section 1 presents study setting, design, sample and sampling method. Section 2 provides information about the study instruments. As there were no valid Vietnamese instruments to measure study variables, the detailed process of developing
Vietnamese versions of the instruments and examining the psychometric properties of these versions of the instruments is described in Section 3 of this chapter. Section
4 presents the procedure to collect data. Section 5 presents the plan for data management and data analysis. The final section summarises Chapter 3 and provides a link to Chapter 4.
3.1 DESIGN, SETTING, SAMPLE AND SAMPLING METHOD
To address Study 1’s objectives, a cross-sectional design was chosen for Study
1. Study 1 was conducted in Suburb 9, Tay Thanh Ward, Tan Phu District, Ho Chi
Chapter 3:Research methods – Study 1 51
Minh City, Vietnam. This suburb has a significant number of people from various areas in Vietnam.
To determine if the Vietnamese versions of the study instruments had acceptable internal consistency and test-retest reliabilities among older women in
Vietnam, a convenience sampling method was applied in this study. The recruitment criteria included: (1) Vietnamese women; (2) aged 60 years and above; (3) able to communicate in Vietnamese; and (4) able to give informed consent.
To examine internal consistency reliabilities and test-retest reliabilities among a sample of older women in Vietnam a minimum of 30 participants were required
(Waltz, Strickland, & Lenz, 2010). To plan for missing data across the month of data collection (10%), 33 participants were proposed as a sample size for this study.
3.2 RESEARCH INSTRUMENTS
Table 3.1 summarises the structured self-reported questionnaire set, which was used to collect data on a range of variables. Details of the research instruments are also presented below.
3.2.1 Socio-demographic characteristics In terms of socio-demographic characteristics, data about age, marital status, employment status, estimated total average income, and highest level of education were collected. Participants were asked their year of birth. It was then calculated in years and kept as a continuous variable. Participants were also asked to indicate if they were single, married, or lived with their partners, or were widowed, separated, or divorced; and to indicate if they were currently employed (part-time, full-time or casual job), retired, or doing housework, or too sick to work
Chapter 3:Research methods – Study 1 52
Table 3.1: Summary information about study instruments
Names of the instruments Number Number Internal Test-retest Population where the Study variables of items of consistency correlation instruments were validated domains value Socio-demographic characteristics: Age, Marital status, Highest level of education, Employment status and Income (5 items) Stressful life Life stressors checklist – revised 30 1 0.73 0.52- 0.95/ in In 198 community-based events (LSC-r) (Wolfe & Kimerling, 1997) about 7 days women and 217 Columbian apart Spanish speaking women in the community. Perceived stress Perceived stress scale-10 (Cohen, 10 1 0.78 0.85/ in 2 In different populations 1988) days apart 0.55/ in 6 weeks apart Social support The MOS social support survey 20 4 0.97 0.72-0.78/ 2987 adults with chronic (Sherbourne & Stewart, 1991) one year conditions in USA Lifestyles BMI (height and weight), Diet, Alcohol intake, Caffeine intake, Physical activities, Smoking General Sleep Disturbance Scale (Lee 21 7 0.77- 0.85 Not reported In different populations & DeJoseph, 1992) Depression the CES-D Scale (L. S. Radloff, 20 4 0.85-0.9 0.51-0.67/ 2-8 In different populations 1977) weeks apart HRQOL The Short Form 12 (SF-12) (Ware et 12 2 0.79 PCS=0.89 In different populations al., 1996) MCS=0.76 Chronic disease: Hypertension, chronic heart diseases, stroke, T2DM, breast cancer, arthritis, osteoporosis and depression (8 items).
Chapter 3:Research methods – Study 1 53
Being employed was defined as having a job or business; or working without pay in a family business for a minimum of one hour per week. Participants were then asked to indicate if their total average income was less than 1,600,000VND/ month (low), or between 1,600,000-9,000,000 00 VND/ month (average), or more than 20,000,000
VND/ month (high); and to indicate the highest education level they had completed from the categories of: Bachelor or Post Graduate degree from University, Diploma from a college, graduated from vocational school, high school, secondary school or primary school, or no schooling.
3.2.2 Stressful life events and perceived stress To measure stress, there are several measurements available, including the
Social Readjustment Rating Scale (Holmes & Rahe, 1967) and the List of
Threatening Experiences (Brugha, Bebbington, Tennant, & Hurry, 1985). These measurements can be classified into three subgroups: environmental approach measurements, which include the scales measuring number of events (stressors); response approach measurements, which include scales measuring the biological responses (stress responses); and psychological approach measurements, which include the scales the appraisals of the stressors (perceived stress). Each type of measurement has its own strengths and limitations. As the focus of this research was women, the LSC-r (Wolfe & Kimerling, 1997) was used to collect data about stressful life events.
The Life Stressors Checklist (revised) (Wolfe & Kimerling, 1997) consists of
30 self-reported groups of lifetime trauma exposure, including life events that are not usually considered but are important stressors in women’s lives such as natural disasters, sexual or physical assault and illness or the death of a relative. Trauma
Chapter 3:Research methods – Study 1 53
researchers report that the use of lists of trauma events and separate inquiries about each is advantageous in that they help to focus memory and facilitate recall of events
(Wolfe & Kimerling, 1997). This instrument is scored in three ways to examine the frequency, severity and influence of SLEs (Wolfe & Kimerling, 1997). First, the frequency of lifetime trauma exposure is calculated by summing one point for each positively endorsed stressor item. This allows the score for LSC-r to range from zero to 30, with higher LSC-r scores indicating the greater number of SLEs that the individual has experienced.
In addition, the influence of SLEs on the person in the past years is examined using a 5-point Likert-type scale response. The answers are rated from 1(no impact at all) to 5 (extreme effect on their life). The scores for LSC-r therefore ranged from 30 to 150. The higher the LSC-r score, the more stress the individual had experienced about the stressors during the previous year. The Cronbach’s alpha for this instrument on 198 community-based women was 0.73 (Wolfe & Kimerling, 1997).
The test- retest reliability of LSC-r has ranged from moderate to good with kappa correlations of 0.52 to 0.95 (Wolfe & Kimerling, 1997). The criterion related validity on 198 community-based women was good (Wolfe & Kimerling, 1997). This instrument has also been validated in 217 community based Colombian Spanish- speaking women (Humphreys. et al., 2011).
However, Cohen (1988; 2015) has suggested that measuring stress as an appraisal of events rather than measuring the events themselves is likely to be sensitive, reliable and less limited to a specific group of participants or contexts. So, stress appraisal instruments have been widely used in a variety of research settings
(Lee et al., 2013; Richardson et al., 2012; Tom & Berenson, 2013). Therefore, the
Chapter 3:Research methods – Study 1 54
Perceived Stress Scale (PSS-10) (Cohen, 1988) was also used to measure perceived stress in this research. The Perceived Stress 10 item Scale (PSS-10) (Cohen, Tom, &
Robin, 1983) is one popular stress appraisal instrument . The PSS was originally developed as a 14-item self-report instrument using 5-point Likert scales. In each question the respondent is asked how often they have experienced particular thoughts and feelings during the last month. A shorter 10-item version was developed for better psychometric quality and for efficiency, as it can be administered in only a few minutes and is easy to score. The PSS-10 is also easily understood. Thus, the PSS-10 is recommended for use in both practice and research (Cohen, 1988; Lee, 2012). The answers range from 0 (never) to 4 (very often). The PSS-10 scores are obtained by reversing the scores on four positively stated items (items 4, 5, 7 and 8), and then summed across all 10 items. Total possible scores for the Perceived Stress Scale range from 0 to 40. The higher the PSS score, the more likely it is that the individual perceived that environmental demands exceeded their ability to cope. The PSS-10
Scale has demonstrated acceptable reliability on 2,387 respondents in the United
States with a Cronbach’s alpha of 0.78 (Cohen, 1988). The PSS-10 has also been validated and used widely in different populations and 20 languages, including
American English (Ezzati et al., 2014; Golden-Kreutz, Browne, Frierson, &
Andersen, 2004; A. M. Mitchell, Crane, & Kim, 2008; Roberti, Harrington, &
Storch, 2006; Smith, Rosenberg, & Timothy Haight, 2014), Thai (Wongpakaran &
Wongpakaran, 2010), Chinese (Leung, Lam, & Chan, 2010; Ng, 2013; Z. Wang et al., 2011), Brazilian (Reis, Hino, & Anez, 2010), Greek (Andreou et al., 2011),
Arabic (Chaaya, Osman, Naassan, & Mahfoud, 2010), Turkish (Örücü & Demir,
2009), French (Lesage, Berjot, & Deschamps, 2012), European Spanish (Remor,
Chapter 3:Research methods – Study 1 55
2006), Persian (Maroufizadeh, Zareiyan, & Sigari, 2014), Serbian (Jovanovic &
Gavrilov-Jerkovic, 2015), Korean (Lee, Chung, Suh, & Jung, 2015), Mexican
Spanish, Portuguese, Danish, Norwegian, Hebrew, Italian, German, Hungarian,
Malayalam, Tamil, Sinhala, Polish, Urdu, and Finnish (Cohen, 2015). Its internal consistency reliability using Cronbach’s alpha ranges from 0.67 to 0.91 and its test- retest reliability ranges from 0.53 to 0.83 (Ezzati et al., 2014; Jovanovic & Gavrilov-
Jerkovic, 2015). The PSS-10 has also been found to provide better predictions for psychological symptoms, physical symptoms and utilisation of health services than other similar instruments (Cohen, 1988, 2015).
3.2.3 Social support
To examine social support, the Medical Outcome Study (MOS) social support survey (Sherbourne & Stewart, 1991) was used. This instrument consists of 20 self- report items of social support experience, including emotional, information support, tangible support, positive interaction, and affection, with an item asking about the number of supporters that the women had when they needed it, and 19 items on a 5- point Likert-type scale response (Sherbourne & Stewart, 1991). The participants are asked to rate each item to describe how often the listed support is available to him/her if he/she needs it (Sherbourne & Stewart, 1991). The answers range from one (none of the time) to five (all of the time). The total possible scores for social support range between 19 and 95. Higher scores represent more social support experienced. The MOS social support survey has reported Cronbach’s alpha of 0.97
(Sherbourne & Stewart, 1991).
Chapter 3:Research methods – Study 1 56
3.2.4 Modifiable lifestyle factors
Participants were measured for their weight and height by the researchers, from which BMI was calculated. WHO has proposed a different cut off for Asian people (Shiwaku, Anuurad, Enkhmaa, Kitajima, & Yamane, 2004), with BMI ≥23 indicating overweight , ≥ 30 indicating obese but there is still limited evidence to support this proposal (Huang et al., 2006). For comparison purpose, the study used the cut-off for Western people and the participants were categorised as being underweight (BMI <18.5), normal weight (18.5 ≤ BMI ≤ 24.9), overweight ( 25.0 ≤
BMI ≤ 29.9) or obese (BMI ≥ 30)(World Health Organization, 2013a).
To collect data about healthy diet, alcohol consumption, caffeine consumption, general physical activity and exercise, and tobacco consumption, standard questions about modifiable lifestyle factors from the AIHW were used
(Australian Institute of Health and Welfare, 2010). Participants were asked about their frequency of consuming vegetables, fruit, alcohol, and caffeine, doing physical activity and exercise, smoking tobacco, and the amount of vegetables, fruit, alcohol, caffeine, physical activity and exercise, and cigarettes they had had in the last week
(Australian Institute of Health and Welfare, 2010).
To assess sleeping habits, the General Sleep Disturbance Scale (GSDS) (Lee
& DeJoseph, 1992) was used. This instrument consists of 21 self-report items with an
8-point Likert-type scale response. Questions pertain to a variety of general sleep disturbances in the last seven days, including: problems initiating sleep, waking up during sleep, waking too early from sleep, quality of sleep, quantity of sleep, fatigue and alertness at work, and the use of substances to induce sleep. Participants are
Chapter 3:Research methods – Study 1 57
asked how many days they had experienced the issue in the last seven days. The answers are rated from 0 (never) to 7 (everyday). The scoring of three items (4, 10, and 11) were reversed, and then summed across all 21 items. Total possible scores for the General Sleep Disturbance Scale ranged from 0 to 147. Overall, a total score of 43 or above represented general sleep disturbance (Lee & DeJoseph, 1992). In subscales, the average score of 3 or above represented some degree of sleep disturbance. Cronbach’s alpha for the GSDS in a previous study was 0.88 (Lee &
DeJoseph, 1992). This instrument has also been validated in other diverse patient populations with a Cronbach’s alpha for this instrument ranging from 0.77 - 0.85
(Lee, 2007; Lee & DeJoseph, 1992).
3.2.5 Depressive symptoms, health-related quality of life, and chronic disease
To assess depressive symptoms, the CES-D Scale was used (L. S. Radloff,
1977). This is a 20 self-report item instrument on a 4-point Likert-type scale response. This instrument includes one item on sleep disturbance. The instrument measures frequency of depressive symptoms over the past week. Participants are asked to rate each item to describe how many days they felt or behaved in the identified ways in the previous week. The answers are rated from 0 (less than 1 day) to 3 (5-7 days). The scoring of positive items (4, 8, 12, and 16) is reversed. The possible range of scores is zero to 60, with higher scores indicating the presence of more symptoms. Scores between 16 and 26 suggest mild depression, and scores ≥ 27 suggest major depression (Tannenbaum, Ahmed, & Mayo, 2007). From previous studies, the Cronbach’s alpha for this instrument ranged from 0.85-0.9 (L. S. Radloff,
1977), and the test-retest reliability of the CES-D Scale determined in 2-week, 4- week, 6-week, and 8-week intervals were 0.51, 0.67, 0.59 and 0.59, respectively (L.
Chapter 3:Research methods – Study 1 58
S. Radloff, 1977). This instrument has also been validated in a wide variety of different general populations and showed similar reliability and validity (Jo, Park, Jo,
Ryu, & Han, 2007; Tannenbaum et al., 2007).
To measure HRQOL the Short Form 12 (SF-12) (Jenkinson & Layte, 1997) was used. The SF-12 is a self-report questionnaire, including 12 questions for eight dimensions of health: general health (1 item), mental health (2 items), physical functioning (2 items), bodily pain (1 item), role limitation related to physical health problems (2 items), role limitation due to emotional health problems (2 items), vitality (1 item) and social functioning (1 item). The SF-12 is scored using a standard scoring procedure and this allowed the score for the whole scale to range from 0 to 100 for the Physical Component Scores (PCS) and the Mental Component
Scores (MCS). The Cronbach’s alpha for this instrument has been reported as 0.79
(Ware et al., 1996). The SF-12 has demonstrated good test-retest reliability with PCS
= 0.89; MCS = 0.76 (Ware et al., 1996). The SF-12 has been used in several studies for different populations, including people with chronic disease, and older adults in a retirement community, and has demonstrated good reliability and validity across a variety of populations (Gandhi et al., 2001; Globe, Levin, Chang, Mackenzie, &
Azen, 2002; Ion et al., 2011; Jenkinson, Chandola, Coulter, & Bruster, 2001; Ware et al., 1996).
Participants were also asked to self-report whether they had ever been diagnosed with one or more of the following conditions: hypertension, coronary heart disease, stroke, T2DM, breast cancer, arthritis, osteoporosis, and depression
(Begg et al., 2007; Irwin et al., 2012).
Chapter 3:Research methods – Study 1 59
The CES-D Scale (Radloff, 1977) and the SF-12 (Jenkinson & Layte, 1997) have been used in Vietnamese populations before while other scales such as the
LSC-r (Wolfe & Kimerling, 1997), MOS social support survey (Sherbourne &
Stewart, 1991), Perceived Stress Scale (PSS-10) (Cohen, 1988), and the GSDS (Lee
& DeJoseph, 1992) had not been used in Vietnam. There is a lack of valid instruments in Vietnam to measure the interested variables. For the comparison purposes, these instruments, which had been used to collect data in Australia, were then chosen to collect data in Vietnam.
3.3 PROCESS TO DEVELOP THE VIETNAMESE VERSIONS OF THE INSTRUMENTS
As there were no valid Vietnamese versions of the above instruments (as shown in Table 3.1), the next section presents a detailed process for developing
Vietnamese versions of these instruments. A summary of the process to develop the
Vietnamese versions of the instruments is presented in Figure 3.1. A focus group discussion to ensure the cultural adaptation for the instruments was not conducted for the Vietnamese versions because the researcher wanted to keep the same measurement instruments to collect data in Vietnam and Australia for comparison purposes. It was recognised that this may be a limitation of the study but the benefit of being able to compare data internationally was given priority.
The English versions of the above instruments were translated using standard translation-back translation processes (Cha, Kim, & Erlen, 2007). In this process, two independent bilingual translators translated the English version into Vietnamese.
After the independent forward English-Vietnamese translation was completed, a
Chapter 3:Research methods – Study 1 60
Preparation Chose and formatted the instruments
Step 1 Independent forward translation
Step 2 Meeting for an agreement in forward translation
Step 3 Translation equivalence assessment
by Vietnamese English speaking experts
Step 4 Face validity assessment for wording revision
Step 5 Independent back translation
Step 6 Meeting for an agreement in back translation
Step 7 Translation equivalence assessment
by native English speaking experts
Step 8 Internal consistency reliability, test-retest reliability
Figure 3.1: Procedure to develop and validate the Vietnamese version of the study instruments
The experts’ comments were also taken into account in the review, modified by a group of bilingual translators and the researcher in order to maximise the
Chapter 3:Research methods – Study 1 61
content validity of the instrument. Following this, the Vietnamese versions of the consensus meeting among the two translators and the bilingual researcher was arranged to achieve agreement on the final Vietnamese version.
Next, the Vietnamese version was sent to three bilingual experts to examine the translation equivalence between the Vietnamese versions and the English versions. These experts gave their opinion on whether the language used in this version was accurate, clear, and culturally appropriate for older women in Vietnam.
Each of the experts independently rated the items on a 5-point Likert scale (one = strongly disagree, five = strongly agree) for the language used in translation. The percentage of experts’ agreement was used for evaluating the translation equivalence.
Instruments were trialled in Vietnamese older women to examine the clarity and understandability of the language used (face validity) and to estimate the time required for an interview. Then, the agreed Vietnamese version was then back translated into English by two independent translators. After the independent
Vietnamese-English back-translation was applied, a consensus meeting among the two translators and the bilingual researcher was arranged to achieve agreement on the English back-translation. Following this, the back-translation version was then used to compare with the original English version to examine the difference between these versions by the bilingual researcher and two native English-speaking experts.
Because there was a constraint of time and resources for this research, and the scales used in this study have been developed and validated in previous studies, when the translation and back-translation procedure was completed the Vietnamese version was only examined for internal consistency and test-retest reliability at a
Chapter 3:Research methods – Study 1 62
month apart in a pilot study. For the purpose of testing internal consistency and test- retest reliability of the Vietnamese versions of the instruments, a cross-sectional design and convenience sampling method were used to collect data from 33 participants.
3.4 PROCEDURE TO COLLECT DATA
In Vietnam, the Elders’ Union is an organisation that organises and manages community activities for people aged 60 and over in their catchment areas. Each branch of the union has lists and contacts of all older people, no matter if they are members or not, in their catchment area. The internal activities among the branches are managed in their hierarchical structure. Activities with external organisations need permission from the presidents of their communities at relevant levels. From outside of the organisation, to work with the target wards’ Elder Unions, it was necessary to have permission and referrals from the presidents of the relevant management level.
The researcher, a lecturer at the University of Medicine and Pharmacy
(UMP), Ho Chi Minh City, Vietnam, contacted the president of the University of
Medicine and Pharmacy, Ho Chi Minh City, Vietnam to obtain his introduction letter to the presidents of the research suburbs. Once the letter had been obtained, the researcher contacted the president of the community to introduce herself and her project, and ask for acceptance and support in data collection within their catchments. After that, the president of the community connected the researcher with the president of the Elder’s Union for their further research-related support.
Chapter 3:Research methods – Study 1 63
After receiving referrals from the president of the ward to the Elders’ Union, the researcher introduced her and the project and requested a list of older women living within the research area and their contact details from the Elders’ Union.
Women who satisfied the selection criteria were informed of the study and invited to participate. The Elders’ Union have the trust of the older people in the Commune.
The president of the Elders’ Union helped to introduce the researcher to older women in the Elder Union’s management at their residential places. Information packages were given to potential participants and included the study information, which explained the purpose of the study, the process for participation, the right to refuse and discontinue study participation, and consent forms. Women who wished to participate in the study registered with the president of the Elders’ Union.
Once informed consent had been obtained, data collection with the questionnaire set was undertaken at two times, a month apart from each other, in interviews at the participant’s house or the community office. As the variety of education levels and vision capacities was obvious among the potential participants, instead of letting the participants self-complete the questionnaire, the researcher and her research assistants had to administer the data collection by using the questionnaire to interview the participants. Four research assistants were Kinh-
Vietnamese, and experienced in research data collection. Research assistants received training by face-to-face meetings and role plays of the interview procedure.
Extra guidance was given directly or through phone when needed. Random checking by the researcher was performed during their data collection for quality control.
Advantages of using face-to-face interview to administer the data collection were the ability to use a long questionnaire, limiting missing data, and increasing
Chapter 3:Research methods – Study 1 64
response rates as the participants could get a harmonious interaction and atmosphere of increased human warmth, and so trust could be increased.
In terms of privacy and safety for the participants, interviews were not done when other people were nearby. Interviews were done in working hours, when other people at the participants’ house had usually gone out to work and or to study. The interview could also be done in the community office with only the participants and the interviewer having a private conversation. Also, as the participants had the researcher’s contact details and name they contacted each other and arranged an appropriate time for the private research interview.
3.5 DATA MANAGEMENT AND ANALYSIS
Each completed questionnaire was given a study ID. The completed questionnaire was then entered into the statistical software. The statistical package for social science software SPSS (Statistical Package for the Social Sciences) 23.0,
AMOS (Analysis of Moment Structures) 23.0 was used for data entry and analysis
(Armonk, 2013).
To check the data entry for coding errors, invalid responses and missing data, the researcher conducted random proofreading of 10% of the data files by comparing them with the original questionnaire, as well as visual checking, descriptive checking and preliminary data analysis (range and logic check) (Pallant, 2010). Any error found in the data file was then double checked against the original data.
An outline of the procedure to manage missing data is presented in Figure
3.2. When the amount of missing data was less than 2.5%, multiple data imputation
Chapter 3:Research methods – Study 1 65
was then done (Howell, 2012). When the amount of missing data was more than
2.5%, the determination was made as to whether missing data were missing completely at random (MCAR) or missing at random (MAR) or missing not at random (MNAR) so as to justify the missing data treatment (Howell, 2012).
If missing data in one variable was not related to the values of other variables, these missing data were considered as MCAR(Howell, 2012). If missing data in one variable was not related to the values of other variables after controlling for some variables, these missing data were considered to be MAR (Howell, 2012). To check whether the missing data were related to values in other variables, the variables having missing data were recoded into ‘0’ and ‘1,’ ‘0’ was entered for groups of cases with no missing data in those variables, while ‘1’ was entered for groups of cases with missing data in that variable. Then the generalised linear model was run to determine if there were significant differences in other variables. For variables with
MCAR or with MAR, multiple data imputation was then done (Howell, 2012).
When the missing data were not MNAR, correlations between variables with missing data and variables showing significant differences were examined. If this correlation was small, multiple data imputations were done (Howell, 2012). If this correlation was large, two data analyses were conducted for the dataset with the missing data and the complete data. If the results from the two analyses were not substantially different, either result was used for reporting and interpretation.
Otherwise, the missing data were reported as a study limitation.
Study 1 tested internal consistency and test-retest for reliability across time.
First, Kolmogorov Smirnova and Shapiro-Wilk tests were used to examine the
Chapter 3:Research methods – Study 1 66
distribution of the sample. The level of significance was set at α=0.05 (Pallant,
2010). Then, the descriptive analysis, such as minimum, maximum, median, mean, and standard deviation, was used as appropriate to describe the continuous variables, and frequency and percentage were used for categorical variables (Pallant, 2010).
Minimum, maximum, and median were used to describe the continuous variables that were not normally distributed, while mean and standard deviation were used to describe the continuous variables that were normally distributed. Next, Chi square,
Fisher’s exact test, t tests, and Mann-Whitney U tests were used to test whether there were differences between older women in Time 1 and Time 2 in terms of social- demographic characteristics. The Chi squared test or Fisher’s exact test (when there were low number cells) were used to examine the association between two categorical variables. Independent t tests were used to examine the association between a binary variable and a normally distributed continuous variable. Mann-
Whitney U tests were used to examine the association between a binary variable and a non-normally distributed continuous variable. Prior to performing statistical analysis, the statistical assumptions were examined.
In terms of internal consistency reliability, values in the Vietnamese version for each overall scale were assessed using Cronbach’s alpha values. Test-retest reliability for the Vietnamese version for each scale was assessed using a Pearson correlation if it was not highly skewed or using the Spearman rho value if it was highly skewed. The instrument was considered to have good internal reliability when it had a Cronbach’s alpha of 0.7 or above (Pallant, 2010). Reasonable test-retest reliability of .50 or above was used (Terwee et al., 2007). The significance level was set at α = .05.
Chapter 3:Research methods – Study 1 67
Missing data < 2.5%? Yes No Data imputation Missing completely at random? Yes No Data imputation Missing at random?
Yes No Data imputation Small correlation?
Yes No Data imputation 2 analyses: similar results?
Yes No Either result will be Missing data will used to report be reported as a study limitation
Figure 3.2: Procedure to manage missing data (Howell, 2012)
Chapter 3:Research methods – Study 1 68 3.6 SUMMARY
This research included three studies to examine SLEs, modifiable lifestyle factors,
depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and
Australia. Study 1 involved standard translation and back-translation processes to translate a questionnaire from English to Vietnamese to gather data on SLEs, perceived stress, social support, modifiable lifestyle factors, HRQOL and chronic disease. In this study, experts’ comments were used in this process for translation evaluation and face validity. The study also asked participants for their thoughts about the meaning and language used in the questionnaire to further evaluate the face validity of the Vietnamese versions of the instruments. In addition, Study 1 also assessed study feasibility, and examined the internal consistency reliability and test-retest correlation reliability at a one-month interval for the
Vietnamese versions of six instruments: The LSC-r; the General Sleep Disturbance Scale; the
Perceived Stress Scale-10 (PSS-10); the CES-D Scale; the MOS social support survey; and the Short Form 12 (SF-12) among older women in Vietnam who met the same criteria as the potential participants for Study 2, the main survey. This chapter presents methods used for
Study 1, including study setting, design, sample, sampling method, information about the
study instruments, procedure to collect data, and plan for data management and data analysis.
The next chapter will present the findings of Study 1.
Chapter 3:Research methods – Study 1 69
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1
Study 1 involved translating a questionnaire from English to Vietnamese to gather data on SLEs, perceived stress, social support, modifiable lifestyle, HRQOL and chronic disease, and examining the translation equivalence, face validity, internal consistency reliabilities and test-retest reliabilities of the Vietnamese versions of the instruments among older women in Vietnam (n=33). This chapter presents the findings of Study 1. This chapter has three sections. Section 1 presents the findings on the translation equivalence and face validity of the instruments and research data collection feasibility. Section 2 presents the findings on internal consistency and test-retest reliabilities of the Vietnamese versions of the selected instruments. Finally, Section 3 summarises the findings of Study 1 and provides the link between Study 1 and Study 2.
4.1 TRANSLATION EQUIVALENCE, FACE VALIDITY OF THE VIETNAMESE VERSIONS OF THE INSTRUMENTS, AND STUDY FEASIBILITY
Overall, the study found that all three bilingual language experts agreed that the translation had been done well and that all of the Vietnamese versions of the instruments achieved good translation equivalence with their English versions. The language used in the
Vietnamese instruments was clear for potential participants. However, to optimise the quality of data collection, the experts also recommended a minor change for the questionnaires which were used to collect data in Vietnam. To be specific, an expert indicated that examples in item 27a (Moderate activities, such as moving a table, pushing a vacuum cleaner, bowling, or playing golf) were generally not relevant to Vietnamese culture. This expert explained that
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 70
Vietnamese older women were not familiar with vacuuming; golfing, or bowling and more
relevant activities should be replaced in this item. This comment was reviewed and modified
by the researcher to “moving a table or something which weighed about 10-15kg.”
Another expert was also concerned about the feasibility of data collection for items asking about portions of vegetables and fruit, particularly for participants from low educational backgrounds. This expert advised that rather than asking the participants to
estimate how many portions of vegetables and fruit they had daily, it was better to ask them
the amount of vegetables and fruits in terms of approximate weight, numbers of bowls and
kinds of vegetables and fruits. Then the data collectors would estimate the number of portions
the participants consumed on average. This suggestion was also taken up by the researcher.
So, in order to prepare for this estimation, more detailed guidelines of how to estimate
numbers of vegetable and fruit portions that participants had were added into the questionnaire to collect data in Vietnam.
In addition, there were some questions raised about items of SLEs which asked about
“being forced to touch someone in sexual ways or have sex.” The expert was concerned whether the word “someone” here included the participant’s partner or husband. She explained that Vietnamese women may understand it did not include their partners and husbands. The research student took this comment into account and notified her participants that these items would include the participants’ partners and husbands during data collection.
After revisions based on the comments from the three experts, the Vietnamese version of the instruments was back-translated to English. The back-translation version was then compared with the original English version by the bilingual researcher and two Australian experts to examine the differences between the versions. As a result of the back translation, additional revisions were made. Specifically, the term of “felt like going to die” in item 46i which asked whether the participant “ever had a very serious physical or mental illness (for
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 71
example cancer, heart attack, serious operation, felt like going to die, hospitalised because
severe neurological diseases)” had been translated into Vietnamese as “cảm giác giống như
sắp chết” (feel like I nearly died). This was advised by an Australian expert to revise to “cảm
thấy muốn chết” (had an idea of death) for better language equivalence between the English
version and Vietnamese version. Therefore, the revision was done to complete the translation
and back-translation procedure.
When the translation and back-translation procedures were completed, the Vietnamese
version of the questionnaire was trialled on three participants, who had the same participation
criteria of those who would participate in the main study. This was to check the face validity
of the Vietnamese version of the questionnaire. This trial found that the Vietnamese version
of the questionnaire was clear for the potential participants. In terms of time, the trial indicated that data collection was feasible given that about 45-70 minutes would be required for data collection via each interview depending on the participant’s education level and health status.
4.2 THE INTERNAL CONSISTENCY AND TEST-RETEST CORRELATION RELIABILITIES OF THE VIETNAMESE VERSION OF THE INSTRUMENTS
To determine the psychometric characteristics of the Vietnamese version of the instruments, the survey was then piloted on 33 participants. Data collection was conducted twice in a month. First, the Vietnamese version of the instruments was used to collect data from the 33 participants to examine the internal consistency reliabilities of the study instruments. As two participants stopped the data collection in the middle of the interview in
Time 1 of Study 1 for personal issues, the data analysis for Study 1 at Time 1 was therefore
conducted on 31 participants. As the continuous variables, did not have normal distributions,
instead of mean and standard deviation, median, minimum, and maximum were used to
describe the variables. Overall, at Time 1 of Study 1, the participants were aged 60 to 84
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 72
years (Median= 71), consumed an average of 3.0 serves of vegetables, 1.0 serves of fruit, 0.5 drink of caffeine a day. No participant reported drinking alcohol, and only one participant reported of smoking. Participants reported an average overall physical activity level of 4 from a possible score of 10. The participants appeared to have an average of 2.0 chronic conditions
(minimum=0, maximum=4) among the chronic conditions of hypertension, heart disease, stroke, T2DM, breast cancer, arthritis, osteoporosis, and depression. The majority of participants were married or lived in a partnership (61.3%, n=19), had Buddhism as a religion
(61.3%, n=19), had completed primary school or less (64.5%, n =20), were not currently employed (77.4%, n = 24) and had a low income (61.3, n =19). About one fourth of women were overweight or obese (29.1%, n = 9). After a month, the instruments were used again on the same 31 participants who had completed the first round of questionnaires before to assess test-retest reliability values of the study instruments. In this retest, 3 participants could not attend the appointment without notice. Due to a restricted timeframe for data collection, data analysis for test-retest reliabilities was then performed on 28 participants. Table 4.1 presents the characteristics of the participants in Study 1 at these two time points.
Table 4.1: Descriptive characteristics of the participants in Study 1 at two time points
Median (range) Median (range) Variable Time 1 (N=31) Time 2 (N=28) Age 71 (60-84) 70 (60-84)
Number of serves of vegetables consumed per day 3.0 (0-10) 2.0 (0-10)
Number of serves of fruit consumed per day 1.0 (0-5) 1.25 (0-5)
Number of alcohol drinks per day 0 0
Number of caffeine drinks per day 0.5 (0-4) 1.0 (0-3)
Number of tobacco cigarettes smoked per day 0 (0-3) 0 (0-4)
Self-rating physical activities 4.0 (1-8) 4.0 (0-10)
Number of chronic conditions 2.0 (0-4) 2.0 (0-4)
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 73
Variable Median (range) Median (range) N (%) N (%) Marital status
Single (never married) 0 0 Married/ partnered 19 (61.3) 15 (53.6) Widow/divorced/separated* 12 (29.0) 13 (46.4) Religion
None 6 (19.4) 7 (25.0) Buddhism 19 (61.3) 16 (57.1) Catholic 4 (12.9) 3 (10.7) Others 2 (6.0) 2 (7.2) Highest educational achievement
Primary or less 20 (64.5) 18 (64.3) Junior school 5 (16.1) 4 (14.3) Senior school 4 (12.9) 4 (14.3) Diploma 0 (0) 0 University or college 2 (6.5) 2 (7.1) Employment status
Currently employed 7 (22.6) 7 (25.0) Not currently employed 24 (77.4) 21 (75.0) Average month income* *
Low (about < 80 USD) 19 (61.3) 12 (42.9) Middle (about 80- <450 USD) 9 (19.0) 14 (50.0) Rather high (about 450 - <1000 USD) 2 (6.5) 2 (7.1) High (about ≥ 1000 USD) 0 (0) 0 (0) BMI
Underweight (<18.5 kg/m2) 1 (3.2) 3 (10.7) Normal (18.5-25 kg/m2) 21 (67.7) 20 (71.4) Overweight (25-29.9 kg/m2) 6 (19.4) 3 (10.7) Obese (≥30 kg/m2) 3 (9.7) 2 (7.1) * One woman had become a widow in the month of research data collection **Income categories derived from the national tax payment standard
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 74
To test the internal consistency values for the Vietnamese versions of the study
instruments, the Cronbach’s alpha values were calculated. It was found that the overall
internal consistency of the Vietnamese version of the LSC-r was 0.67; the Vietnamese
version of the Perceived Stress Scale (V-PSS-10) was 0.80; the Vietnamese version of the
General Sleep Disturbance Scale was 0.81; the Vietnamese version of the CES-D Scale was
0.90; the Vietnamese version of the MOS social support survey was 0.96; the Vietnamese
version of the Short Form 12 was 0.88. Details of these internal consistency values for older
women in Vietnam in comparison with the internal consistency values found in previous
studies are presented in Table 4.2
Pearson correlation values were assessed for the Vietnamese versions of the study
instruments. As the GSDS measured sleep over a week, the result across a month was
expected to change and therefore less likely to correlate with time 1’s results. Therefore, test-
retest at one-month interval was not conducted on the Vietnamese version of this scale. Apart
from GSDS, the study found that overall test-retest reliability of the Vietnamese version of
the LSC-r was 0.67; the Vietnamese version of the Perceived Stress Scale (V-PSS-10) was
0.54; the Vietnamese version of the CES-D Scale was 0.86; the Vietnamese version of the
MOS social support survey was 0.59. The test-retest of the Vietnamese version of the SF-12
was 0.41 for physical component score and 0.84 for mental component score across the
month. Details of these test-retest correlation values for older women in Vietnam in
comparison with the test-retest reliability values of the instruments found in previous studies are presented in Table 4.3.
Chapter 4: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 75 Table 4.2: Internal consistency reliabilities of the Vietnamese versions of the instruments in comparison with the internal consistency values of the instruments found in previous studies
Study variables Instruments translated Number Cronbach’s Cronbach’s of items alpha in alpha in previous this study 1 studies (n=31) Stressful life events Life stressors checklist – revised (LSC-r) (Wolfe & Kimerling, 1997) 30 0.73 0.67
Perceived stress Perceived stress scale-10 (PSS-10) (Cohen, 1988) 10 0.67-0.91 0.80
Sleeping disturbance General Sleep Disturbance Scale (GSDS) (Lee & DeJoseph, 1992) 21 0.88 0.81
Depression CES-D Scale (L. S. Radloff, 1977) 20 0.85-0.9 0.90
Social support MOS social support survey (Sherbourne & Stewart, 1991) 20 0.97 0.96
Health-related quality of life Short Form 12 (SF-12) (Ware et al., 1996) 12 0.79 0.88
Chapter 4:Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 76
Table 4.3: Test-retest reliabilities of the translated instruments in comparison with the test-retest reliability values of the instruments found in previous studies
Study variables Instruments translated Number Test-retest Test-retest of items correlation correlation in in the Study previous 1 (n=28) studies Stressful life events Life stressors checklist – revised (LSC-r) (Wolfe & Kimerling, 1997) 30 0.52-0.95 0.67
Perceived stress Perceived stress scale-10 (PSS-10) (S. Cohen, 1988) 10 0.55-0.85 0.54
Sleeping disturbance General Sleep Disturbance Scale (GSDS) (Lee & DeJoseph, 1992) 21 Not given -
Depression CES-D Scale (Radloff, 1977) 20 0.51-0.67 0.86
Social support MOS social support survey (Sherbourne & Stewart, 1991) 20 0.72-0.78 0.59
Health-related quality of life Short Form 12 (SF-12) (Ware et al., 1996) 12 PCS=0.89 0.41
MCS=0.76 0.84
Chapter 5: Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 77 4.3 SUMMARY
This research included three studies. Study 1 translated the questionnaire measuring socio-demographic characteristics, SLEs, perceived stress, modifiable lifestyle factors, social support, depression, HRQOL and chronic diseases into
Vietnamese. Some of the variables were measured with a few items while others were measured using validated scales. For the validated scales, Study 1 examined the psychometric properties of the Vietnamese versions of the instruments for use among older women in Vietnam. Data were collected at two time points, one month apart from each other. The study found that the Vietnamese versions of the instruments attained very good translation equivalence and were clear for older women in
Vietnam. The alpha coefficients of the Vietnamese versions of all instruments used in this research passed 0.7, except for the Vietnamese version of the LSC-r (0.67).
Test-retest reliability coefficients of the Vietnamese version of these instruments also met the desired values (0.50), except for the test-retest correlation of PCS (0.41).
Findings from Study 1 suggested that the Vietnamese versions of the research instruments could be used for data collection in Study 2, which was the main survey about SLEs, perceived stress, modifiable lifestyle factors, depressive symptoms,
HRQOL, and chronic disease among older women in Vietnam. By using these
Vietnamese versions of the instruments, the research could provide a comprehensive description about stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL and number and prevalence of chronic disease among older women in Vietnam for the first time. The next chapter will present the methods of Study 2.
Chapter 4:Translation equivalence and psychometric properties of the Vietnamese versions of the research instrument: Results of Study 1 78
Chapter 5: Research methods – Study 2
Study 2 aimed to describe SLEs, perceived stress, social support, modifiable lifestyle, HRQOL and prevalence of chronic disease among older women in
Vietnam. The study also explored the influence of SLE on modifiable lifestyle factors, HRQOL and chronic disease among older women in Vietnam and the potential roles of social support and perceived stress on the relationship between
SLEs and health among older women in Vietnam. The study answered the following research questions: (1) what are the SLEs, level of perceived stress, social support, modifiable lifestyle factors, health related quality of life and chronic disease reported by older women in Vietnam? (2) How and to what extent are the SLEs associated with modifiable lifestyle factors, HRQOL and chronic disease among older women in Vietnam? (3) To what extents do perceived stress and social support mediate the influence of SLEs on health among older women in Vietnam? This chapter presents the research methods for Study 2 and has three sections: Section 1 presents the study design, setting, sample and sampling methods; and Section 2 presents the study instruments, data collection, management and analysis. The final section summarises the research methods used in Study 2 and provides a link to the next chapter.
5.1 DESIGN, SETTING, SAMPLE AND SAMPLING METHOD
5.1.1 Design To address the research objectives and answer the research questions stated in
Chapter 1, a cross-sectional design was chosen. This design allowed the researcher to describe the study variables at the concurrent time and explore the associations among variables (Bowling, 2009). This design was also relatively inexpensive and
Chapter 5: Research methods – Study 2 79
required the participants to make only a one-off contribution (Bowling, 2009). These factors contributed to the study’s feasibility.
5.1.2 Setting Study 2 was conducted in 16 rural and urban suburbs in Vietnam. In terms of urban area, the study collected data from 8 urban suburbs in Ho Chi Minh City. This city is located in the southeast of Vietnam and has a population of 7,681,700 people, including 4,034,000 females and 469,525 older people (aged 60+), living in 3666 km2 (Vietnamese General Statistic Office, 2012). The city has the largest economy and the biggest financial sector in Vietnam and attracts a significant number of immigrants from various provinces. In terms of rural areas, the study collected data from 8 rural suburbs in Dong Thap province. This province is located in the Mekong
River Delta with a population of 1,676,300 people, including 841,100 females, living in 496 km2 (Vietnamese General Statistic Office, 2012).
5.1.3 Sample and sampling methods Study 2 required a relatively large sample size because it used Structural
Equation Modelling analysis techniques to demonstrate the pathways by which SLEs influence health among older women in Vietnam. Ideally, a sample is calculated based on the formula 20*k with k being the number of free parameters (Kline, 2005).
However, it has also been stated that a ratio between the number of parameters and the sample size of 1:10 is more realistic (Kline, 2005). This study potentially had 59 parameters, including 15 variables (number of SLEs, impact of SLEs, perceived stress, vegetable consumption, fruit consumption, physical activity, alcohol drinking, smoking, sleeping, BMI, social support, depression, mental health, physical health and number of chronic diseases) and 44 associations across these variables.
Therefore, the expected sample size for this study was 59 × 10 = 590. However, as it
Chapter 5: Research methods – Study 2 80
was unlikely that all variables considered in the theoretical model would be significant, and to ensure the study was feasible in terms of time and funding, a sample of 400 was deemed to be sufficient. Also, literature suggested that a sample of 400 could be enough to provide stable specific modifications of the model
(Cunningham, 2009). To allow for potentially missing data (10%), 440 participants were proposed as the study’s sample size. The same criteria were applied to recruit the study participants in Study 1 and Study 2. However, the 33 participants of Study
1 were excluded from participating in Study 2. In order to address Study 2’s objectives, a stratified random sampling method was used to recruit women from 16 suburbs in urban and rural areas in Vietnam. Figure 6.1 provides an outline of sample procedures in Vietnam for Study 2.
In Vietnam, the estimated ratio of older people living in urban areas and rural areas was about 1:2. To maximise the generalisation of the sample for the
Vietnamese population, this ratio was applied to decide the approximate number of participants living in urban areas and those living in rural areas. This meant the approximate number of participants living in urban areas was 440/3=147 and the approximate number of participants living in rural areas was 293. There were 16 selected suburbs: eight urban and eight rural. The eight urban suburbs were located in Ho Chi Minh City, while the eight rural suburbs were located in Dong Thap province. In the selected urban suburbs, there were 1,967 older people, including
1,147 women. On the other hand, in the selected rural suburbs, there were 1875 older people, including 1,096 women. In order to choose approximately 147 older women living in urban areas and 293 older women in rural areas, simple random sampling was conducted from lists of older people, which were provided by the leaders the
Elders’ Unions.
Chapter 5: Research methods – Study 2 81
Vietnam (3 areas: 8 regions; 59 provinces + 5 metropolitan cities)
South (2 regions: South East + Mekong River Delta)
South East (HCMC) 8 selected urban suburbs
Mekong River Delta (Dong Thap) 8 selected rural suburbs
16 suburbs Random sampling
on the Elders’ Union list
Figure 5.1: Outline of sampling procedure in Vietnam
5.2 RESEARCH INSTRUMENT, PROCEDURE FOR DATA COLLECTION, PLAN FOR DATA MANAGEMENT AND ANALYSIS
The same research instruments and procedure to collect data that were used in
Study 1 were applied to Study 2. In brief, data collection was conducted with support from the Elders’ Unions. The Unions have lists and contacts of all older people, in their catchment areas, no matter if they are members or not. Therefore, contacting the older women in Vietnam through Elders’ Unions captured most the older women in the research areas. First, the researcher contacted her employer to obtain an introduction letter to the presidents of the research suburbs. Once the letter had been obtained, the researcher contacted the presidents of the communities to introduce herself, her project, and ask for acceptance and support in data collection within their catchments. After that, the presidents connected the researcher with the presidents of the Elders’ Unions for their further research-related support. After receiving referrals from the presidents of the wards to the Elders’ Unions, the researcher introduced her and the project and requested a list of older women living within the research area and their contact details from the Elders’ Unions.
After randomly sampling, the researcher asked the leaders of the Elders’
Union for help in inviting the potential participants to join in the research. This
Chapter 5: Research methods – Study 2 82
process was applied until the sample size for Study 2 was met. The majority of people aged 60 and above in Vietnam register themselves in the Elders’ Unions. The
Elders’ Unions have the trust of the older people in the Commune. The presidents of the Elders’ Unions also helped to introduce the researcher to older women living under their management at their residential places. With this recruitment strategy, adequate numbers of participants were recruited. The study was conducted with older women who were able to give informed written consent after considering the study information. There was no coercion in this recruitment process.
Women who satisfied the selection criteria were informed of the study and invited to participate. Potential participants were given information packages that included the following study information: explanation of the purpose of the study; the process for participation, the right to refuse and discontinue study participation and consent forms. Women who wished to participate in the study registered with the presidents of the Elders’ Unions. Once informed consent had been obtained, data collection with the questionnaire set was undertaken at two time points, a month apart from each other, during interviews at the participant’s house or the community office by the researcher and research assistants.
The same procedures to enter and clean data that were used for Study 1 were applied for Study 2 prior to data analysis. To check for normality, the Kolmogorov
Smirnova and Shapiro-Wilk tests were used. The data can be determined as normally distributed when the significance of this test is p> 0.05 (Pallant, 2010). To check for outliers, descriptive analyses were used (Pallant, 2010). Descriptive analyses such as minimum, maximum, median, mean, and standard deviation were used to describe the continuous variables as appropriate, and frequency and percentage were used for category variables (Pallant, 2010).
Chapter 5: Research methods – Study 2 83
To test the hypothesised model and develop the model describing the influence of SLEs on modifiable lifestyle factors, HRQOL, and chronic disease among older women in Vietnam, bivariate analyses (Pearson correlation, Spearman rho test as appropriate) and structural equation modelling statistical analysis were used (Kline, 2005). The Pearson rho correlation was used to examine the association between two normally distributed continuous variables and the Spearman rho test was used to examine the association between two non-normally distributed continuous variables. Structural equation modelling statistical analysis was used to describe the direct and indirect influences among variables. SEM has an advantage over traditional multivariate statistical analysis as it allows researchers to explore further the direct and indirect relationships among study variables (Kline, 2005). In addition, this statistical analysis method also takes into account the error of measurement (Kline, 2005). Moreover, SEM tests the goodness of fit between the hypothesised model and the study data (Kline, 2005). Therefore, SEM is a sophisticated method to provide the answer for the study research questions. Prior to performing structural equation modelling, the statistical assumptions of normal distribution and outliers were examined (Kline, 2005; Pallant, 2010).
A good fitting model is one which achieves the fit indices: (1) non-significant
χ2 test; (2) 1 <χ2/df < 2 and ; (3) Root Mean Square Error of Approximation
(RMSEA) <0.05 and PCLOSE > 0.05; Goodness of Fit Index (GFI) > 0.9; (4)
Adjusted Goodness of Fit Index (Adjusted GFI) > 0.9; (5) Standardized Root Mean
Square Residual (SRMR) <0.06 (Kline, 2005). In this study, even though p value and a χ2 /df are the traditional measure for evaluating overall model fit, they are very sensitive to sample size (Bollen, 2014). Therefore, they were not used in the model
Chapter 5: Research methods – Study 2 84
evaluation in this study, but were reported for completeness (Beckstead, Yang, &
Lengacher). The level of significance was set at α=0.05 (Pallant, 2010).
5.3 SUMMARY
Study 2 described SLEs, social support, perceived stress, modifiable lifestyle,
HRQOL, and the number and prevalence of chronic disease among older women in
Vietnam (n=440). The study also explored the influence of psychosocial stress on modifiable lifestyle, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. Further, the study examined the potential roles of social support and perceived stress on the relationship between SLEs and modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in
Vietnam. Chapter 5 presented the study methods of Study 2, including information about the study setting, design, sample, sampling methods, and plan for data analysis for the main survey. The next chapter will present the results regarding SLEs, perceived stress, social support, modifiable lifestyle factors, HRQOL and prevalence of chronic disease, the influence of SLEs on modifiable lifestyle factors, HRQOL and chronic disease, and potential roles of social support and perceived stress on the relationship between SLEs and health among older women in Vietnam.
Chapter 5: Research methods – Study 2 85
Chapter 6: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2
Chapter 6 presents the results of Study 2. The chapter has three sections.
Section 1 describes the socio-demographic characteristics, stressful life events
(SLEs), perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL and prevalence of chronic disease among older women in
Vietnam. As the continuous variables in Study 2 were not normally distributed, instead of using the mean and standard deviation, this description uses the median, minimum, and maximum. Section 2 presents findings on the influence of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL and the number of chronic diseases, and the roles of social support and perceived stress on the relationship between SLEs, and modifiable lifestyle factors, depressive symptoms, HRQOL and the number of chronic diseases among the Vietnamese older women. Section 2 also presents findings on the role of perceived stress on the relationship between SLEs and modifiable lifestyle factors, depressive symptoms,
HRQOL and the number of chronic diseases. Structural Equation Modelling (SEM) was used to model this influence. As the assumption of normal distribution in SEM was violated, an Asymptotic Distribution Free estimator (ADF) and the Bollen-Stine bootstrap p function were used to adjust chi-square for non-normality in AMOS. The final section presents a summary of the findings from Study 2.
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 286
6.1 DESCRIPTIONS
6.1.1 Socio-demographic characteristics
Table 6.1 presents the socio-demographic characteristics of the Vietnamese older women, who participated in Study 2. The participants were 440 women aged between 60 and 94 years (median = 68 years old) (attrition rate = 84.8%). The majority of them lived in rural areas (70.9%, n=312), lived with their partners or husbands (50.5%, n = 222), completed primary school or less (75.4%, n =322), were not currently employed (70.4%, n = 330), and had low incomes (53%, n=233). Few women were single (2.5%, n=11), or had a diploma or university education level
(3.6%, n = 16), or high income (3.2%, n= 14).
Table 6.1: Socio-demographic characteristics of the Vietnamese older women (n=440)
Variable N (%) Age (median (range) 68 (60-94) Living areas Rural 312 (70.9) Urban 128 (29.1) Marital status Single (never married) 11 (2.5) Married/ partnered 221 (50.2) Widow/divorced/separated 208 (47.3) Highest educational achievement Primary or less 334 (75.9) Junior school 59 (13.4) Senior school 31 (7.0) Diploma, university 16 (3.6) Currently employed 131 (29.8) Average month income* Low (about < 80 USD) 233 (53.0) Middle (about 80- <450 USD) 189 (43.2) Rather high (about 450 - <1000 USD) 12 (2.7) High (about ≥ 1000 USD) 2 (0.5) *Income categories derived from the national tax payment standard
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 287
6.1.2 Stressful life events
Stressful life events (SLEs) were measured by the Life Stressors Checklist
(revised) (Wolfe & Kimerling, 1997). First, the participants were asked to nominate if they had experienced any SLEs from a list of 29 lifetime traumas. The older
Vietnamese women reported a range of 0-22 SLEs, out of 29, with a median of 4
SLEs. Table 6.2 provides more details about the reported SLEs. As seen in Table
6.2, the most commonly reported SLEs among the sample included: losing a loved one (93.6%, n = 412); abortion or miscarriage (48.9%, n =215); serious money problems (42.3%, n = 186); serious physical or mental illness (35.2%, n = 155); or experiencing a natural disaster (31.6%, n = 139). Several older Vietnamese women also reported experience of some form of violence (either physical, emotional or sexual) (30%, n=130; 13.4%, n=59, 10.9%, n=48, respectively), having a handicapped child or caring for close people with some severe health problems
(24.3%, n = 107), or having close family members or herself serve time in jail (13%, n=44 or 3%, n=10). The LSC-r (Wolfe & Kimerling, 1997) also asked the participants to indicate the magnitude of the impact of the SLE on them in the previous year on a 5-point Likert-type scale (from 1, “not at all,” to 5, “extremely”).
This produced a total possible score from 29 to 145. Among the older Vietnamese women, the total impact scores in the previous year ranged from 29-54 with a median of 31. As seen in Table 6.2, those who experienced caring for a close person with a serious health problem (30.5%, n=25), having a handicapped child, (52.0%, n=13), having a close person die unexpectedly (17.6%, n=22), witnessing of a serious accident (22.0%, n=13), having a physical attack by someone known to them (23.2%, n=13), emotional abuse or neglect (25.0%, n=15), or being in jail (38.5%, n=5) were more likely to report a lot or severe impact of SLEs during the
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 288 Table 6.2: Stressful life events reported by Vietnamese older women (n=440)
Experienced ever Impact in the past 12 months 1 2 3 4 5
not at all some extremely n (%) N (%) n (%) n (%) n (%) n (%) 1 Serious disaster 139 110 9 14 2 4 (31.6) (79.1) (6.5) (10.1) (1.4) (2.9)
2 Witnessed serious accident 59 28 5 13 1 12 (13.4) (47.5) (8.5) (22.0) (1.7) (20.3)
3 Experienced serious accident 70 39 2 18 3 8 (15.9) (55.7) (2.9) (25.7) (4.3) (11.4)
4 Close family member in jail 44 33 1 6 1 3 (10.0) (75.0) (2.3) (13.6) (2.3) (6.8)
5 Sent to jail 13 6 0 2 2 3 (3.0) (46.2) (0.0) (15.4) (15.4) (23.1)
6 Been put in foster care or put up for adoption 24 20 1 2 1 0 (5.5) (83.3) (4.2) (8.3) (4.2) (0.0) 7 Parents separated or divorced while living with them 10 7 0 3 0 0 (2.3) (70.0) (0.0) (30.0) (0.0) (0.0) 8 Separated or divorced 38 33 0 2 0 3 (8.6) (86.8) (0.0) (5.3) (0.0) (7.9) 9 Serious money problems 186 150 4 10 10 12
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 89
(42.3) (80.6) (2.2) (5.4) (5.4) (6.5) 10 Serious physical or mental illness 155 81 10 34 9 21 (35.2) (52.3) (6.5) (21.9) (5.8) (13.5) 11 Emotionally abused or neglected 60 35 3 7 5 10 (13.6) (58.3) (5.0) (11.7) (8.3) (16.7) 12 Physically neglected 13 6 1 0 3 2 (3.0) (46.2) (7.7) (0.0) (23.1) (15.4) 13 Experienced abortion or miscarriage (lost your baby) 215 196 8 7 1 3 (48.9) (91.2) (3.7) (3.3) (0.5) (1.4) 14 Separated from your child against your will 12 8 0 2 0 2 (2.7) (66.7) (0.0) (16.7) (0.0) (16.7) 15 Your child with a severe physical or mental handicap 25 5 1 5 2 11 (5.7) (20.0) (4.0) (20.0) (8.0) (44.0) 16 Caring for close one with a severe physical or mental handicap 82 47 2 8 9 16 (18.6) (57.3) (2.4) (9.8) (11.0) (19.5) 17 Close one died suddenly or unexpectedly 125 71 7 25 9 13 (28.4) (56.8) (5.6) (20.0) (7.2) (10.4) 18 Someone close to you died (not suddenly) 412 336 21 38 6 11 (93.6) (81.6) (5.1) (9.2) (1.5) (2.7) 19 Witnessed violence between family members (before age 16) 12 10 0 1 0 1
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 90
(2.7) (83.3) (0.0) (8.3) (0.0) (8.3) 20 Seen a robbery, mugging, or attack taking place 31 23 1 3 3 1 (7.0) (74.2) (3.2) (9.7) (9.7) (3.2) 21 Been robbed, mugged, or physically attacked by strangers 33 18 1 6 3 5 (7.5) (54.5) (3.0) (18.2) (9.1) (15.2) 22 Physically attacked by someone you knew (before age 16) 3 2 0 1 0 0 (0.7) (66.7) (0.0) (33.3) (0.0) (0.0) 23 Physically attacked by someone you knew after 16 56 36 1 6 5 8 (12.7) (64.3) (1.8) (10.7) (8.9) (14.3) 24 Bothered or harassed by sexual remarks, demands at work/school 4 4 0 0 0 0 (0.9) (100.0) (0.0) (0.0) (0.0) (0.0) 25 Forced to be touched or touch someone in a sexual way (before 16) 2 1 0 0 0 1 (0.5) (50.0) (0.0) (0.0) (0.0) (50.0) 26 Forced to be touched or touch someone in a sexual way after 16 5 4 0 0 1 0 (1.1) (80.0) (0.0) (0.0) (20.0) (0.0) 27 Forced to have sex (before age 16) 1 0 0 0 0 1 (0.2) (0.0) (0.0) (0.0) (0.0) (100.0) 28 Forced to have sex after 16 36 20 0 9 3 3 (8.2) (55.6) (0.0) (25.0) (8.3) (8.3) 30 Other event experienced by someone close to you 41 8 1 11 4 17 (9.3) (19.5) (2.4) (26.8) (9.8) (41.5)
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 91 previous year. Many older women (51.3%, n=21) also reported a lot or severe impact of SLEs which had not happened to them but people close to them. Interestingly, among those who experienced SLEs, many older women in Vietnam reported no impact from the SLEs during the previous year. For example, the majority of those who experienced disasters (79.1%, n=110), money problems (80.6%, n=150), abortion or miscarriage (91.2%, n=196), had a close person in jail (75%, n=33) reported no impact of these events during the previous year.
The Life Stressors Checklist (revised) (Wolfe & Kimerling, 1997) has one open-ended item (item 29) which asked the participants to indicate any SLEs which the list did not mention but they wanted to talk about. Responding to this item, the older women (33.6%, n=148) indicated several SLEs related to their children (20.2%, n=89), husband (6.4%, n=28), extended family (3.3%, n=14) or war-related SLEs
(4.3%, n=19). SLEs related to children included: studying/ working far away from home (0.9%, n=4), disobeying his/her mother (3.2%, n=14), upsetting his/her mother verbally (3.6%, n=16), getting drunk (2.5%, n=11), gambling (0.2%, n=2), leaving home (1.1%, n=5), destroying housewares because of being drunk or getting angry (0.7%, n=3), having problems at work including getting bankrupt or being fired (0.7%, n=3), being in debt and mother having to pay for him/her (0.7%, n=3), having low income (0.5%, n=2), not being married (0.7%, n=3), having more than one partner (0.2%, n=1), having quarrels (0.9%, n=4) or broken up with his/her partner (0.5%, n=2), taking care of grandchild because their parents left them after separation (0.7%, n=3), dispute over property share (4.3%, n=19), looking down on the mothers (0.2%, n=1), prohibiting women to visit (0.2%, n=1), being beaten by others (1.1%, n=5), being sick, (0.9%, n=4), not having any one to care for them when she passes away (0.5%, n=2).
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 92
Husband-related SLEs included: having quarrels (2.5%, n=11), getting drunk
(1.4%, n=6), gambling (0.2%, n=1), shouting at wife (0.9%, n=4), fighting with others or beating children (0.5%, n=2), not wanting to work (0.2%, n=1); having other partners when she was still living with him (0.5%, n=2), not agreeing to divorce and threating to beat her for her request to divorce (0.2%, n=1). Extended- family-based SLEs included: having quarrels, fighting, no love among family members (2.1%, n=9) and disputing property shares (1.1%, n=5). War-related SLEs included witnessing bombing, or shooting (2.7%, n=12), being injured, or tortured in jail (0.9%, n=4), witnessing a family member who was killed (0.5%, n=2), and death threats (0.2%, n=1). Few women reported SLEs related to low compensation for giving house/ land to make way for a street (0.2%, n=1), feeling of being a burden to children (0.2%, n=1), low family socio-demographic background (0.5%, n=2), and being alone (0.9%, n=4).
The study also used the Perceived Stress Scale (PSS-10) (Cohen, 1988), asking participants to indicate their frequency of experiencing particular thoughts and feelings over the previous month on a 5-point Likert scale (0 [never] to 4 [very often]) with a possible score of 0-40. Table 6.3 provides details about perceived stress reported by the Vietnamese older women. Perceived stress scores ranged between 0 and 34 with a median of 6.5. The majority of older women reported never feeling angry because things happened out of their control (90.9%, n=400), never felt not able to overcome difficulties (83.6%, n=368), never felt stress (80.2%, n=353), and never felt upset because of unexpected things (74.3%, n=327).
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 293 Table 6.3: Perceived stress reported by Vietnamese older women (n=440)
Never Almost never Sometimes Fairly often Very often During the last month, how often have you…? n (%) n (%) n (%) n (%) n (%) 1. been upset because of something that happened unexpectedly? 327 (74.3) 13 (3.0) 61 (13.9) 27 (6.1) 12 (2.7)
2. felt that you were unable to control the important things in your life? 296 (67.3) 13 (3.0) 52 (11.8) 47 (10.7) 32 (7.3)
3. felt nervous and “stressed”? 353 (80.2) 8 (1.8) 51 (11.6) 15 (3.4) 13 (3.0)
4. felt confident about your ability to handle your personal problems? 71 (16.1) 4 (0.9) 49 (10.7) 66 (15.0) 252 (57.3)
5. felt that things were going your way? 30 (6.8) 6 (1.4) 53 (12.0) 83 (18.9) 268 (60.9)
6. found that you could not cope with all the things that you had to do? 353 (80.2) 16 (3.6) 45 (10.2) 20 (4.5) 6 (1.4)
7. been able to control irritations in your life? 210 (47.7) 8 (1.8) 41 (9.3) 63 (14.3) 111 (26.8)
8. felt that you were on top of things? 24 (5.5) 8 (1.8) 47 (10.7) 94 (21.4) 267 (60.7)
9. been angered because of things that were outside of your control? 400 (90.9) 8 (1.8) 27 (6.1) 4 (0.9) 1 (0.2)
10 felt difficulties were piling up so high that you could not overcome them? 368 (83.6) 8 (1.8) 42 (9.5) 15 (3.4) 7 (1.6)
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 94 6.1.3 Social support
Social support was measured using the MOS social support survey (Sherbourne
& Stewart, 1991). This scale included one item (item 1) asking for the number of supporters that the women had when needed. The participants in this study reported to have 0-50 supporters, with a median of 2 supporters. Still, about one tenth (11.1%) of older Vietnamese women did not have any supporters. The scale also included 19 items (items 2-20) on a 5-point Likert-type scale response asking about the frequency of support available when they needed it. Responses ranged from 1 (none of the time) to 5 (all of the time) and the total scores for social support ranged between 19 and 95 with a median of 72. Table 6.4 provides further social support data among the participants on these 19 items. Around a third of the women reported having no one to talk with about their problems (26.4%, n=116), no one to keep their mind off things (33.0%, n=145), and no one to share their most private worries and fears with
(39.1%, n=172). About a quarter of the older Vietnamese women reported not having any supporter to understand their problems (24.3%, n=107), nor to give them information to help them to understand the situation (20.7%, n=91), nor to give them good advice (28.4%, n=125). One in five did not have any one to talk to when needed (17.3%, n=76). A small percentage of the women (8.2%, n=36) had no one to help when they were confined to bed.
6.1.4 Modifiable lifestyle characteristics
Participants were asked to report their vegetable, fruit, alcohol, caffeine and tobacco consumption, physical activity level, and exercise status. As seen in Table
6.5, in general, the participants had 3 serves of vegetables and 2 serves of fruit daily.
Only one third of the participants reported having 5 or more serves of vegetables daily (38.9%, n = 171), or 2 serves of fruits daily (38.0%, n = 167).
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 95 Table 6.4: Social support reported by Vietnamese older women (n=440)
How often is each of the following kinds 1 2 3 4 5 of support available to YOU if you need n (%) n(%) n (%) n (%) n (%) it?
2. Someone to help you if you were 36 2 18 35 130 221 confined to bed (8.2) (4.1) (8.0) (29.5) (50.2) 3. Someone you can count on to listen 76 28 64 100 172 to you when you need to talk (17.3) (6.4) (14.5) (22.7) (39.1) 4. Someone to give you good advice 125 37 48 95 135 about a crisis (28.4) (8.4) (10.9) (21.6) (30.7) 5. Someone to take you to the doctor if 32 17 32 132 227 you needed it (7.3) (3.9) (7.3) (30.0) (51.6) 6. Someone who shows you love and 68 32 54 108 178 affection (15.5) (7.3) (12.3) (24.5) (40.5) 7. Someone to have a good time with 85 40 55 102 158 (19.3) (9.1) (12.5) (23.2) (35.9) 8. Someone to give you information to 91 41 63 104 141 help you understand a situation (20.7) (9.3) (14.3) (23.6) (32.0) 9. Someone to confide in or talk to 116 28 56 101 139 about yourself or your problems (26.4) (6.4) (12.7) (23.0) (31.6) 10 Someone who hugs you 113 34 34 77 182 (25.7) (7.7) (7.7) (17.5) (41.4) 11 Someone to get together with for 102 41 66 91 140 relaxation (23.2) (9.3) (15.0) (20.7) (31.8) 12 Someone to prepare your meals if 43 17 39 136 205 you were unable to do it yourself (9.8) (3.9) (8.9) (30.9) (46.5) 13 Someone whose advice you really 110 24 64 98 144 want (25.0) (5.5) (14.5) (22.3) (32.7) 14 Someone to do things with to help 145 27 45 89 134 you get your mind off things (33.0) (6.1) (10.2) (20.2) (30.5) 15 Someone to help with daily chores 41 21 39 142 197 if you were sick (9.3) (4.8) (8.9) (32.3) (44.8)
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 96
How often is each of the following kinds 1 2 3 4 5 of support available to YOU if you need n (%) n(%) n (%) n (%) n (%) it?
16 Someone to share your most private 172 31 39 81 117 worries and fears with (39.1) (7.0) (8.9) (18.4) (26.6) 17 Someone to turn to for suggestions 164 34 45 82 115 about how to deal with a personal (37.3) (7.7) (10.2) (18.6) (26.1) problem 18 Someone to do something enjoyable 120 30 48 100 142 with (27.3) (6.8) (10.9) (22.7) (32.3) 19 Someone who understands your 107 30 57 100 146 problems (24.3) (6.8) (13.0) (22.7) (33.2) 20 Someone to love and make you feel 64 27 71 113 165 wanted (14.5) (6.1) (16.1) (25.7) (37.5) * item 1 is an open-ended question, asking for the number of supporters that the women had when needed; **1 None of the time; 2 A little of the time; 3 Some of the time; 4 Most of the time; 5 All of the time
The majority of participants abstained from alcohol (90.2%) and smoking tobacco (98.6%). Their self-rated overall physical activity was 5 on the 0-10 scale (0 representing not at all active and 10 representing extremely active). Many reported at least a moderate physical activity level (63.6%, n=270), but had not participated in exercise in the last month (64.1%, n=282). The participants were also measured for their weight and height, from which BMI was calculated and classified (WHO,
2013). Data shows that about a quarter of the women were overweight or obese
(25.5%, n = 94). The participants’ sleeping habits in the last 7 days were estimated using GSDS (Lee & DeJoseph, 1992), with a total score of 43 or above representing general sleep disturbance (Lee & DeJoseph, 1992). The study found that nearly 40%
(38.9%, n= 171) of older women reported having poor sleep (GSDS ≥43).
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 297 Table 6.5: Modifiable lifestyle characteristics of older women in Vietnam (n=440) Variable Median n (%) (range) Average number of vegetable serves usually 3 (0-12) consumed/ day Average number of fruit serves usually consumed /day 2 (0-10) Having at least of 2 serves of fruit daily 171 (38.9) Having at least of 5 serves of vegetables daily 167 (38.0) Average number of alcohol usually drinks per day 0 (0-2) Drinking alcohol Never 397 (90.2) In the past 15 (3.4) Occasionally 24 (5.5) Regularly 4 (0.9) Average number of caffeine usually drinks per day 0 (0-10) Average number of tobacco usually smoked per day 0 (0-1) Smoking Never 434 (98.6) In the past 3 (0.7) Current 3 (0.7) Self-rating physical activities 5 (0-10) Level of physical activity Very active 64 (14.5) Moderately active 216 (49.1) Mildly active 110 (25.0) Sedentary 50 (11.4) Number of day per week exercised in the past month 0 (0-7) None 281 (63.9) 1-2 a week 13 (3.0) 3-4 a week 8 (1.8) 5-6 a week 5 (1.2) Daily 132 (30) BMI Underweight (<18.5 kg/m2) 33 (7.5) Normal (18.5-25 kg/m2) 295 (67.0) Overweight (25-29.9 kg/m2) 94 (21.4) Obese (≥30 kg/m2) 18 (4.1) Sleep disturbance (GCS ≥ 43) 171 (38.9)
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 98
6.1.5 Depressive symptoms, health-related quality of life, and chronic disease
Table 6.6 presents the information regarding depressive symptoms, HRQOL, and chronic disease in older Vietnamese women who completed the survey.
Depressive symptoms were measured using the CES-D Scale. Scores between 16 and
26 suggest mild depression, and scores ≥ 27 suggest major depression. Based on this criterion, Study 2 found that about a quarter of the older Vietnamese women (24.5%) reported symptoms of mild depression (15.5%, n=68), and 9% reported major depression.
The Short Form 12 (SF-12) (Jenkinson & Layte, 1997) was used to measure
HRQOL. This scale provided a Physical Component Summary (PCS) and a Mental
Component Summary (MCS), which both have possible scores from 0 to 100. The study found that the physical and mental health scores of women in this sample ranged between 10.37 and 61.81 (Median=34.32), and between 17.13 and 69.77
(Median=59.52), respectively.
Participants were also asked to self-report whether they had ever been diagnosed with one or more of the following conditions: hypertension, coronary heart disease, stroke, T2DM, breast cancer, arthritis, osteoporosis, and depression.
The study found that the women had 0 to 6 chronic conditions with a median of 2 chronic conditions. About a half of participants had hypertension (54.3%, n=239) and arthritis (48.4%, n=213). Coronary heart diseases (28%, n=123), osteoporosis
(16.4%, n=72), and T2DM (13%, n=57) also appeared to be frequent health problems among the Vietnamese older women.
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 299
Table 6.6: Depressive symptoms, health-related quality of life, and chronic disease reported by Vietnamese older women (n=440)
Variables N (%)
Depressive symptoms
No depression 332 (75.5) Mild depression 68 (15.5) Major depression 40 (9.0) Physical health Median (Range) 34.32 (10.37-61.81)
Mental health Median (Range) 59.52 (17.13-69.77)
Number reporting chronic conditions Median (Range) 2 (0-6)
High blood pressure 239 (54.3) Coronary heart diseases 123 (28.0) Stroke 18 (4.1) Type 2 diabetes 57 (13.0) Breast cancer 2 (0.5) Arthritis 213 (48.4) Osteoporosis 72 (16.4) Depression 2 (0.5)
6.2 MODELLING THE IMPACT OF STRESSFUL LIFE EVENTS ON MODIFIABLE LIFESTYLE FACTORS, DEPRESSIVE SYMPTOMS, HEALTH RELATED QUALITY OF LIFE, AND CHRONIC DISEASE AMONG OLDER WOMEN IN VIETNAM
The previous section described the socio-demographic characteristics, SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms,
HRQOL and prevalence of chronic disease among Vietnamese older women. This section reports testing the model of the impact of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL and the number of chronic diseases among older women in Vietnam. The testing model included the number of SLEs, the reported influence of SLEs, perceived stress, social support, vegetable consumption, fruit consumption, tobacco smoking, alcohol drinking, sleeping
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2100
disturbance, BMI, depressive symptoms, physical health, mental health, and the number of chronic diseases as variables. This section also tested the roles of social support and perceived stress on the relationship between SLEs and health.
To address these aims, a preliminary study framework (see Figure 6.1), based on
Schwarzer and Schulz’s conceptual model (Schwarzer & Schulz, 2002), was applied.
The model hypothesised that exposure to stressful life events would initiate or reinforce health compromising behaviours such as unhealthy diet, smoking (Krueger et al., 2011; Mainous et al., 2010), excess alcohol consumption (Krueger et al., 2011;
Slopen et al., 2011), sedentary lifestyle (Krueger et al., 2011; Mainous et al., 2010), sleep deprivation (Ware et al., 1996), and elevated BMI (Barry & Petry, 2008). With these health-compromising behaviours, participants may experience worse HRQOL
(Lau, 2013; Renzaho et al., 2013; Staniute et al., 2013; Takei et al., 2012), and be more likely to have a chronic illness (Pyykkönen et al., 2010; Renzaho et al., 2013;
Segerstrom & O’Connor, 2012). In addition, the study hypothesised that people exposed to stressful life events would be more likely to develop depressive symptoms (Renzaho et al., 2013), and this could lead to decreased HRQOL and more chronic conditions (Bajor et al., 2013). Moreover, the study hypothesised that social support could buffer the influence of SLEs and perceived stress (Manuel et al., 2012;
Salgado et al., 2012; Staniute et al., 2013). Finally, the study hypothesised that perceived stress could mediate the influences of the number and influence of SLEs on modifiable lifestyle factors and depressive symptoms (Lee et al., 2013) among
Vietnamese older women.
Chapter 5: Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2101
Figure 6.1: Preliminary study framework about the influences of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 102 First, a binary correlation analysis was undertaken to examine the associations among the variables in the preliminary study framework. As no continuous variables in the preliminary study framework were normally distributed, the Spearman rho test was used to examine the correlation between two continuous variables. Table 6.7 presents the correlations among the study variables. The level of significance was set at α=0.05. The table indicates that there were significant correlations between: the number of SLEs and reported impact of SLEs, perceived stress, overall physical activity level, sleep disturbance, depressive symptoms, physical health, mental health, and number of chronic conditions. The table also shows significant correlations between the impact of SLEs in the previous year and perceived stress, social support, alcohol consumption, sleep disturbance, depressive symptoms, physical health, mental health and number of chronic diseases; and between the perceived stress and social support, vegetable and fruit consumption, sleep disturbance, depressive symptoms, physical health, and mental health. Among the lifestyle factors and depressive symptoms, several correlations existed. Finally, Table
6.7 shows significant correlations between vegetable consumption and physical health; fruit consumption and physical and mental health; overall physical activity level and physical health, the number of chronic diseases; depressive symptoms and physical and mental health and the number of chronic diseases.
Based on the correlation matrix, several non-significant paths were removed from the preliminary framework. The pathways that were removed from the preliminary study framework included: pathways linking number of SLEs and number of vegetable serves per day; number of fruit serves per day; number of alcohol drinks per day; BMI; the pathways linking impact of SLEs in the previous month and number of vegetable serves per day, number of fruit serves per day,
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 103 Table 6.7: Correlation matrix among variables in Vietnamese dataset
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 1. Number of SLEs -
2. Impact of SLEs last year .620**
3. Social support -.083 -.144**
4. Perceived stress .300** .353** -.173**
5. Vegetable serves/day .012 -.074 .128** -.208**
6. Fruit serves/day -.057 -.087 .223** -.239** .440**
7. Alcohol drinks/day -.055 -.106* .050 .005 .035 .037
8. Overall physical activity level .135** .079 .040 -.031 .157** .024 -.007
9. Sleep disturbance .126** .183** -.051 .199** -.184** -.165** .014 -.144**
10. BMI .003 .011 .084 -.084 .123** .102* .027 .041 -.067
11. Depressive symptoms .380** .420** -.169** .612** -.244** -.222** .004 -.050 .519** -.098*
12. Physical health -.131** -.152** .112* -.193** .267** .199** .034 .340** -.435** .024 -.366**
13. Mental health -.241** -.283** .099* -.428** .096* .208** .077 -.059 -.269** .071 -.372** .001
14. No. of chronic disease .144** .158** -.040 .050 .033 -.007 .014 -.153** .247** .266** .206** -.302** -.118* -
** Correlation is significant at the .01 level (2-tailed). * Correlation is significant at the .05 level (2-tailed)
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 104 overall physical activity levels and BMI. The pathways linking perceived stress and numbers of alcohol drinks per day, overall physical activity level, and BMI were also removed from the preliminary study framework.
In addition, the following pathways were also removed: linking the number of vegetable serves and fruit serves consumed per day and the number of chronic diseases; linking alcohol drinks per day and physical health, mental health and number of chronic diseases; pathways linking overall physical activity level and mental health; and pathways linking BMI, physical health and mental health were removed from the preliminary framework. Some significant paths were added to the preliminary study framework, including: pathways linking number of SLEs, the
SLE’s impact the previous year and physical health, mental health, and number of chronic diseases; the pathways linking perceived stress and physical and mental health. These additions allowed the study to investigate the direct influence of the number of SLEs, SLE’s impact in the previous year, perceived stress on physical health and mental health, and the number of chronic diseases. After these modifications, the study’s hypothesised model was finalised (see Figure 6.2). This model, rather than the preliminary study framework, was tested for the goodness of fit between the hypothesised model and the study data.
To test the goodness of fit, SEM was conducted. Prior to performing SEM, the assumptions of SEM were examined and it was found that: there were few random missing data from the Vietnam sample; no variables were normally distributed (p<0.05) and there were no outliers in the dataset. Missing data were imputed using the expectation maximisation functions in SPSS. As the assumption of normal distribution was violated, an ADF and the Bollen-Stine bootstrap p function were used for non-normality in AMOS. SEM was conducted to test the goodness of
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2105
Figure 6.2: Final hypothesised model about the influences of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 106 fit between the hypothesised model and the study data and it was found that the hypothesised model did not fit the study data and model modification was needed to achieve a good fit. The modifications done were not only based on statistical findings including the modification indices and the coefficient results of the paths, but they were also theoretically reasonable. After modifying, the modified model was re-tested for good fitness.
Figure 6.3 presents findings on the final model of the influences of the number and impact of stressful life events and perceived stress on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. The figure also displays standardised path coefficients of the modified model. All paths were significant at p < 0.05. The model was fit with (1) p<0.01; (2) χ2/df=2.11; (3) RMSEA=0.05; PCLOSE =0.47; GFI=0.97; Adjusted
GFI=0.94; SRMR=0.05. These indicators of the test of fit above indicated that the modified model fit the observed data. The figure shows that a number of SLEs indirectly influenced physical health through increasing overall physical activity level (β =0.10, p<0.05). The impact of SLEs in the previous year indirectly influenced physical and mental health and increased chronic disease through increasing sleep disturbance (β =0.13, p<0.05) and depressive symptoms (β =0.10, p<0.05). Perceived stress indirectly influenced physical and mental health and increased chronic disease through decreased vegetable (β =-0.14, p<0.05) and fruit consumption (β =-0.23, p<0.05), increased sleep disturbance (β =0.18, p<0.05) and depressive symptoms (β =0.61, p<0.05). Perceived stress mediated the influence of the number of SLEs (β =0.10, p<0.05) and the SLEs’ impact in the previous year (β
=0.38, p<0.05) on vegetable and fruit consumption, increasing sleep disturbance, depressive symptoms, and mental health.
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2107
Figure 6.3: Final model of the influences of psychosocial stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam with standardized estimates (n=440)
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2 108 Table 6.7 shows that social support was negatively and significantly correlated with reported impact of SLEs in the previous year and perceived stress in the binary correlations matrix. Figure 6.4 further presents findings on the buffering role of social support on the influences of SLEs on perceived stress, depressive symptoms, and mental health among older women in Vietnam with standardized estimates
(n=440). The figure also displays standardised path coefficients of the model. All paths were significant at p < 0.05. The model was fit with (1) p>0.05; (2)
χ2/df=2.13; (3) RMSEA=0.05; PCLOSE =0.42; GFI=0.99; Adjusted GFI=0.97;
SRMR=0.04. These indicators of the test of fit above indicated that the modified model fit the observed data. The figure shows that the more social support people had, the less they perceived stress (β =-0.15, p<0.05), and perceived stress mediated the influence of social support on depression and mental health.
Figure 6.4: Buffering role of social support on the influences of SLEs on health among older women in Vietnam with standardized estimates (n=440)
6.3 SUMMARY
Study 2 described SLEs, level of perceived stress, social support, modifiable lifestyle factors, HRQOL, and the prevalence of chronic disease among older women in Vietnam. In summary, the study found that on average, older women in Vietnam reported 4 of the 29 listed SLEs. The commonly reported SLEs included: losing a
109
loved one (93.6%, n = 412): experience of abortion or miscarriage (48.9%, n =215); serious physical or mental illness (35.2%, n = 155); a natural disaster (31.6%, n =
139); and serious money problems (42.3%, n = 186). Several older Vietnamese women also reported experience of some form of: violence (either physical, emotional or sexual) (30%, n=13; 13.4%, n=59, or 10.9%, n=48 respectively); having a handicapped child; or caring for close people with some severe health problems (24.3%, n = 107). In addition to the 29 listed SLEs, older women in
Vietnam (33.6%, n=148) also indicated several child-related SLEs or husband- related SLEs, extended-family-related SLEs and war-related SLEs. In terms of perceived stress, older women in Vietnam reported a low level of perceived stress with the perceived stress scores ranging between 0 and 34 with a median of 6.5.
The Vietnamese older women who participated in this study also reported to have 0-50 supporters with a median of 2 supporters. The total social support score ranged from 0-82 with a median of 53. There were still about one tenth (11.1%) of older Vietnamese women having no supporter. A few participants reported having 5 or more serves of vegetables daily (38.9%, n = 171), or 2 serves of fruits daily
(38.0%, n = 167). The majority of them abstained from alcohol (90.2%, n=397), and smoking tobacco (98.6%, n=434), had moderate physical activity levels (63.6%, n=270) but had not participated in exercise in the last month (64.1%, n=282). About a quarter of the women were overweight or obese (25.5%, n = 94). Nearly 40%
(38.9%, n= 171) of older women reported having poor sleep (GSDS ≥43). A quarter of the women (24.5%) reported symptoms of mild depression (15.5%, n=68), or major depression (9.1%, n=40). The physical and mental health scores of women in this sample ranged between 10.37 and 61.81 (Median=34.32), and between 17.13
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2110
and 69.77 (Median=59.52), respectively, out of a possible 100. Older women had 0 to 6 chronic conditions with an average of 2 chronic conditions.
Study 2 also explored: the influence of psychosocial stress on modifiable lifestyle, HRQOL and chronic disease; the role of social support on impact of SLEs and perceived stress; and the role of perceived stress on the number and impact of
SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL and the number of chronic diseases among the Vietnamese older women. The study found that a number of SLEs indirectly influenced physical health through increasing overall physical activity level (β =0.10, p<0.05). The impact of SLEs in the previous year indirectly influenced physical and mental health and increased chronic disease through increasing sleep disturbance (β =0.13, p<0.05) and depressive symptoms (β =0.10, p<0.05). Perceived stress indirectly influenced physical and mental health and increased chronic disease through decreasing vegetable (β =-0.14, p<0.05) and fruit consumption (β =-0.23, p<0.05), and increasing sleep disturbance (β =0.18, p<0.05) and depressive symptoms (β =0.61, p<0.05). Perceived stress mediated the impact of the number of SLEs (β =0.10, p<0.05) and the SLEs’ impact in the previous year (β
=0.38, p<0.05) on vegetable and fruit consumption, increasing sleep disturbance, depressive symptoms, and mental health. Binary correlations also show the significant negative correlations between social support and impact of SLEs in the previous year (r =-0.14, p<0.05) and perceived stress (r =-0.17, p<0.05). Modelling showed that (1) the more social support people had, the less perceived stress they had
(β =-0.15, p<0.05), and (2) perceived stress mediated the influence of social support on depression and on mental health.
Since people in different cultures may experience stressful life events, modifiable lifestyle factors, HRQOL, and chronic disease differently, comparisons
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2111
between Australia and Vietnam in terms of stressful life events, modifiable lifestyle factors, HRQOL and chronic disease are necessary to provide a number of practical applications. Such comparison should include consideration of policies, resources and services for older women to manage stress, modify their lifestyle, improve
HRQOL and manage their chronic disease. In addition, to optimise the comparability across cultures, it is important that consideration be given to incorporating the use of consistent research measures. The next chapter will present methods for Study 3, which was a cross-cultural comparison of stressful life events, modifiable lifestyle factors, HRQOL and chronic disease among older women in Vietnam and in
Australia.
Chapter 6:Stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam: Results of Study 2112
Chapter 7: Research methods – Study 3
Study 3 used cross-sectional data for the year 2012 (with permission) from a longitudinal study Healthy Ageing of Women’s (HOW) and performed secondary data analysis to compare with data from Study 2 in Vietnam. Briefly, the longitudinal
Healthy Ageing of Women (HOW) study (CI Anderson) explored the influence of modifiable lifestyle factors on health among women in Australia. Data for this study had been collected in 2001 (HOW1), 2006 (HOW2), 2011 (HOW3) and 2012
(HOW4). In 2012, data collected included modifiable lifestyle factors, HRQOL, depressive symptoms, chronic disease and SLEs. These data were retrieved with permission to compare with the data from Vietnamese women. Study 3 explored the following research questions: (1) what similarities and differences occur in SLEs, modifiable lifestyle factors, HRQOL and chronic disease reported by older women in
Australia and Vietnam?; and (2) What similarities and differences occur in the model describing the direct and indirect influences of SLEs on modifiable lifestyle factors,
HRQOL and chronic disease among older women in Australia and Vietnam?
This chapter first provides a brief introduction to the HOW4 study and the relationship of the current research with HOW4. Then, the research data analysis for
Study 3 is described. Finally, the chapter summarises methods used in Study 3 and provides a link to Chapter 8. Since Study 3 included a comparison of the data from
Study 2 and secondary data from HOW4, the research settings, sample and sampling methods, procedure to collect data, data entry and data cleaning are not described again in the research method section of Study 3.
Chapter 7:Research methods – Study 3 113
7.1 THE RELATIONSHIP OF CURRENT RESEARCH WITH HOW4
Table 7.1: Outline of current research in conjunction with the HOW study
AUSTRALIA VIETNAM
A longitudinal study of the Healthy Stressful life events, modifiable lifestyle
Ageing of Women (HOW study) in factors, depressive symptoms, health- Australia related quality of life, and chronic
disease in older women in Vietnam and
Australia: A cross-cultural comparison
HOW 1-3 conducted at 5-yearly intervals Study 1: Development and validation of in 2001, 2006, 2011 the Vietnamese versions of the research instrument (n = 33)
HOW4 Expanded the current focus of the Study 2 (Main study): Psychosocial HOW study to explore influence of stress, social support, modifiable stressful life events on lifestyle factors, lifestyle factors, depressive symptoms,
HRQOL and chronic disease risk (2012, health-related quality of life, and chronic n = 184) disease among older women in Vietnam
(n = 440)
Study 3: Comparative data analysis of Vietnamese and Australian samples (n = 624) on stressful life events, modifiable lifestyle factors, depressive symptoms, health- related quality of life, and chronic disease among older women in Vietnam and
Australia
*Shading denotes current study
An outline of the current research was presented in conjunction with the HOW study in Table 7.1. The longitudinal HOW study
Chapter 7:Research methods – Study 3 114
(CI Anderson) commenced in 2001 and involved 1,500 randomly selected women from the electoral roll from six selected areas of South-East Queensland, which had a population of 3,050,000 people living on 22, 420 km2, including high and low income people, and people from regional and urban areas. Australian women were invited to participate if they were: (1) Australian citizens; (2) aged 45 to 60 in 2001;
(3) able to communicate in English. Women were not chosen to participate in this study if they: (1) were not able to communicate in English or (2) not able to give informed consent. In 2001, 886 women participated, with a response rate of 59%
(Anderson, Yoshizawa, Gollschewski, Atogami, & Courtney, 2004). HOW data collection was followed up in 2006, 2011, and 2012. There were 564 questionnaires completed and returned in 2006 (Xu, Anderson, & Courtney, 2010); 350 participants in 2011 (Seib, Whiteside, Humphreys, Lee, Thomas, Chopin, Crisp, A. O'Keeffe, et al., 2014), and 184 questionnaires were completed and returned in 2012. HOW data in the years 2001, 2006, 2011, and 2012 focused on modifiable lifestyle factors and
HRQOL among participating women. Data from 2012 (CI Seib and Anderson) also included SLEs and relational conflict from the participating women and collected serum biomarkers and buccal cells. The analysis of the 184 women in HOW 4 (2012) formed the Australian arm of the study, and was used to compare with data from
Vietnam in Study 2.
The same research instruments that had been used in Australia to collect data on socio-demographic characteristics, SLEs, modifiable life style factors, depression,
HRQOL and chronic disease were applied in Study 2 in Vietnam. There were two noted differences in the Australian dataset: (1) in terms of total average incomes, this was categorised as low if the participant earned less than 20,000AUD/year; average if they earned between 20,000 and 80,000AUD/ year; and high if they earned more
Chapter 7:Research methods – Study 3 115
than 80,000AUD/year; (2) when asking about the qualifications among older women, in Australia, TAFE had been used instead of vocational school, as it was in Vietnam.
Even though the name of the educational facilities appears to be different, it was the best equivalent qualification between the two nations’ education systems.
7.2 PLAN FOR DATA ANALYSIS
Parallel data analysis procedures with Study 2 of the Vietnamese study were applied to the secondary data analysis from the Australian dataset. To check for normality, the Kolmogorov Smirnova and Shapiro-Wilk tests were used. The data can be determined as normally distributed when the significance of these test is p>
0.05 (Pallant, 2010). To check for outliers, descriptive analysis was used (Pallant,
2010). Descriptive analyses such as minimum, maximum, median, mean, and standard deviation were used to describe the continuous variables as appropriate, and frequency and percentage were used for category variables (Pallant, 2010).
This study used the Chi square, Fisher’s test, t test, and Mann-Whitney U test to test whether there were differences between older women in Australia and in
Vietnam in terms of social-demographic characteristics, SLEs, modifiable lifestyle factors, depression, HRQOL and chronic disease. The Chi squared test or Fisher’s exact test was used to examine the association between two categorical variables.
Independent t tests were used to examine the association between a binary variable and a normally distributed continuous variable. Mann-Whitney U tests were used to examine the association between a binary variable and a non-normally distributed continuous variable. Prior to performing statistical analysis, the statistical assumptions were examined. The level of significance was set at α=0.05.
To test the hypothesised model and develop the model describing the influence of SLEs on modifiable lifestyle factors, HRQOL, and chronic disease
Chapter 7:Research methods – Study 3 116
among older women in Australia, bivariate analyses (Pearson correlation, Spearman rho test as appropriate) and structural equation modelling statistical analysis were used (Kline, 2005). The Pearson rho correlation was used to examine the association between two normally distributed continuous variables and the Spearman rho test was used to examine the association between two non-normally distributed continuous variables. Structural equation modelling statistical analysis was used to describe the direct and indirect influences among variables. Prior to performing structural equation modelling, the statistical assumptions of normal distribution and outliers were examined (Kline, 2005; Pallant, 2010).
7.3 SUMMARY
Study 3 included findings from the Vietnamese data reported in Study 2
(n=440) and secondary data from 184 Australian women who participated in the
HOW4 study. In Australia, a secondary data analysis was performed on a cross- sectional dataset for the year 2012 from the longitudinal HOW study (CI Anderson and CI Seib), which were derived with permission (n=184) (see Appendix C). Study
3 examined similarities and differences in SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and in Australia. The study also compared the models describing the influence of
SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and in Australia. Chapter 7 has presented the study methods of Study 3. The next chapter will present findings from Study 3.
Chapter 7:Research methods – Study 3 117
Table 7.2: Summary of data analysis plan
Research questions Data analysis method Do the Vietnamese versions of the study Descriptive analysis instruments have the equivalent meaning to Chi square, Fisher’s test, t test, their English versions, and achieve acceptable Mann-Whitney U test, face validity, internal consistency reliabilities, Cronbach’s alpha, Pearson and test-retest reliabilities among older women correlation or Spearman rho as in Vietnam? appropriate Among older women in Vietnam: Descriptive analysis such as What are the SLEs and their reported impact on frequency, percentage, min, the women in the previous year, modifiable max, mean, median, and lifestyle factors’ characteristics, prevalence of standard deviation as those reported symptoms of depression, appropriate. HRQOL, and the number and prevalence of Bivariate correlation (Pearson chronic diseases? correlation or Spearman rho as How and to what extent are the SLEs associated appropriate). with modifiable lifestyle factors, depressive Structural equation modelling symptoms, HRQOL, and chronic disease? statistical analysis. What are the levels of perceived stress and social support? To what extent does perceived stress mediate the influence of SLEs on health and social support buffer the influence of SLEs on perceived stress, depressive symptoms, and mental health? Among older women in Vietnam and Australia: Descriptive analysis What similarities and differences occur in Chi square, Fisher’s test, t test, SLEs, modifiable lifestyle factors, depressive Man-Whitney U test, symptoms, HRQOL and chronic disease? Bivariate correlation (Pearson What similarities and differences occur in the correlation, or Spearman rho as models describing the influence of SLEs on appropriate). modifiable lifestyle factors, depressive Structural equation modelling symptoms, HRQOL and chronic disease? statistical analysis
Chapter 7:Research methods – Study 3 118
Chapter 8: Cross-cultural comparisons: Results of Study 3
Chapter 8 has six sections presenting the results of Study 3. The chapter first compares the socio-demographic characteristics between older women in Vietnam and in Australia. This is followed by a comparison of SLEs among older women in
Vietnam and Australia and also a description of the similarities and differences in modifiable lifestyle factors among these older women. The chapter also describes the reported similarities and differences among the women in relation to depressive symptoms, HRQOL, and chronic disease. Finally, the chapter presents the models describing the influences of the number and impact of SLEs on modifiable lifestyle factors, HRQOL, and chronic disease among the older women participants from both countries. A comparison of the models generated for the older women in both countries is also presented. The chapter concludes with a summary of the findings of
Study 3.
Since the same measurements were used to collect data in Australia and
Vietnam, information about the measurements will not be repeated in this chapter.
However, again, as the continuous variables in Study 3 were also not normally distributed, instead of using mean and standard deviation, and parametric tests, Study
3 used median, minimum, maximum, and nonparametric tests. For the modelling, as the assumption of normal distribution in Structural Equation Modelling was violated, an ADF and the Bollen-Stine bootstrap p function were used to adjust chi-square for non-normality in AMOS.
Chapter 8:Cross-cultural comparisons: Results of Study 3 119
8.1 COMPARISIONS OF SOCIO-DEMOGRAPHIC CHARACTERISTICS
Information about socio-demographic characteristics among older women in
Vietnam and Australia is presented in Table 8.1. Vietnamese women and Australian women had similar prevalence of employment (χ2 (1) =0.6, p>0.05). Apart from this similarity, there were significant differences in age (p<0.01), marital status (χ2 (4) =
51.5, p<0.01), education level (χ2 (5) = 216.9, p<0.01), and income (χ2 (2) = 35.7, p<0.01) between Vietnamese women and Australian women. The Vietnamese women were older than the Australian women (median= 68.0 vs median=65.0)
(p<0.01), and were more than twice as likely to be widowed. The Australian women were more likely to be married or live in a partnership. The majority of Vietnamese women (75.9%, n=334) had completed only primary school or less. In contrast, a greater number of Australian women had completed junior school and above (82.7%, n=148). More than 50% of Vietnamese participants had low incomes. Many
Australian participants did not report their total income (45.7%, n=84), but 35% of those who reported their income reported themselves in a low-income group (n=35).
8.2 COMPARISION OF STRESSFUL LIFE EVENTS
The comparisons of SLEs among the older women in both countries are presented in Table 8.2. The level of significance was set at α=0.05. Overall, there was no significant difference in the number of SLEs among older women in these two nations (p=0.37). The Vietnamese women were more likely to report an experience of a serious disaster (χ2(1) =38.1, p<0.05), having a close family member in jail (χ2(1) =5.8, p<0.05), or self in jail (χ2(1) =5.6, p<0.05), having serious money problems (χ2(1) =82.5, p<0.05), losing a baby (χ2(1) =14.7, p<0.05), having a close person die not suddenly (χ2(1) =12.5, p<0.05), being physically attacked by a known person (χ2(1) =4.5, p<0.05), or being forced to have sex when they were older than
Chapter 8:Cross-cultural comparisons: Results of Study 3 120
Table 8.1: Socio-demographic characteristics of older women in Vietnam (n=440) and Australia (n=184)
In In Differences p level Vietnam Australia n (%) n (%) Age (median) 68.0 65.0 z=-3.6 p<0.01 (range) (60-94) (55-71) Marital status χ2(4) = 51.5 p<0.01 Single (never married) 11 (2.5) 6 (3.3) Married/ Partnered 234 (53.2) 137 (74.5) Widow/divorced/separated 195(44.3) 36 (19.6) Highest educational achievement χ2(5) = 216.9 p<0.01 Primary or less 334 (75.9) 31 (17.3) Junior school 59 (13.4) 63 (35.2) Senior school 31 (7.0) 22 (12.3) Diploma 4 (0.9) 38 (21.2) University or college 12 (2.7) 25 (14.0) Employment status χ2(1) =0.6 p>0.05 Employed 130 (29.6) 44 (24.7) Not currently employed 330 (70.4) 134 (75.3) Average income χ2(2) = 35.7 p<0.01 Low 234 (53.2) 35 (19.0) Middle 188 (42.7) 47 (25.5) High 14 (3.2) 18 (9.8)
16 years old (χ2(1) =4.2, p<0.05). The Australian women were more likely to report an experience of seeing serious accidents (χ2(1) =10.4, p<0.05), having parents separated or divorced when living with them (χ2(1) =19.0, p<0.05), being separated or divorced (χ2(1) =13.7, p<0.05), caring for people with a handicap (χ2(1) =5.3, p<0.05). They were also more likely to report having a close person die suddenly
(χ2(1) =24.7, p<0.05), seeing domestic violence (χ2(1) =14.8, p<0.05), being
Chapter 8:Cross-cultural comparisons: Results of Study 3 121 Table 8.2: Stressful life events among older women in Vietnam (n=440) and Australia (n=184)
SLEs In Vietnam In Australia Differences p n (%) n (%) level Number of SLEs (median (range)) 4 (1-15) 4 (0-18) z= -0.89 0.37 1. Serious disaster 138 (31.4) 14 (7.8) χ2(1) =38.1 <0.01 2. Seen serious accident 61 (13.9) 44 (24.6) χ2(1) =10.4 <0.01 3. Had very serious accident 71 (16.1) 27 (14.8) χ2(1) =0.2 0.72 4. Close family member to jail 45 (10.2) 8 (4.3) χ2(1) =5.8 <0.05 5. To jail 13 (3.0) 0 (0.0) χ2(1) =5.6 <0.05 6. Be put in foster care or put up for adoption 24 (5.5) 7 (3.8) χ2(1) =0.7 0.54 7. Parents separate or divorce while your living with them 10 (2.3) 19 (10.3) χ2(1) =19.0 <0.01 8. Separated or divorced 38 (8.6) 35 (19.1) χ2(1) =13.7 <0.01 9. Serious money problems 187 (42.5) 10 (5.4) χ2(1) =82.5 <0.01 10. Very serious physical or mental illness 155 (35.2) 57 (31.1) χ2(1) =1.0 0.35 11. Emotionally abused or neglected 62 (14.1) 32 (17.5) χ2(1) =1.22 0.33 12. Physically neglected 12 (2.7) 7 (3.8) χ2(1) =0.5 0.45 13. Had an abortion or miscarriage (lost your baby) 213 (48.4) 58 (31.7) χ2(1) =14.7 <0.01
122
14. Separated from your child against your will 12 (2.7) 2 (1.1) χ2(1) =1.6 0.37 15. Your child with a severe physical or mental handicap 25 (5.7) 9 (4.9) χ2(1) =0.1 0.85 16. Caring of close one with a severe physical or mental handicap 82 (18.6) 49 (26.9) χ2(1) =5.3 <0.05 17. Close one died suddenly or unexpectedly 126 (28.6) 88 (48.1) χ2(1) =24.7 <0.01 18. Someone close to you died (not suddenly) 415 (94.3) 157 (85.8) χ2(1) =12.5 <0.01 19. < 16yrs, seen violence between family members 12(2.7) 27 (14.8) χ2(1) =31.9 <0.01 20. Seen a robbery, mugging, or attack taking place 31 (7.0) 15 (8.2) χ2(1) =0.2 0.62 21. Been robbed, mugged, or physically attacked by strangers 35 (8.0) 30 (16.3) χ2(1) =9.7 <0.01 22. <16yrs, been physically attacked by someone you knew 3 (0.7) 30 (16.3) χ2(1) =63.2 <0.01 23. >16yrs, been physically attacked by someone you knew 57 (13.0) 13 (7.1) χ2(1) =4.5 <0.05 24. bothered or harassed by sexual remarks, jokes, demands by s.o at work/school 4 (0.9) 14 (8.2) χ2(1) =20.8 <0.01 25. <16yrs, being forced to be touched or touch someone in a sexual way 1 (0.2) 28 (15.2) χ2(1) =65.8 <0.01 26. >16yrs, being forced to be touched or touch someone in a sexual way 5 (1.1) 11 (6.0) χ2(1) =12.3 <0.01 27. <16yrs, being forced to have sex 1 (0.2) 10 (5.4) χ2(1) =20.3 <0.01 28. >16yrs, being forced to have sex 37 (8.4) 7 (3.8) χ2(1) =4.2 <0.05 29. Others SLEs 150 (34.1) 30 (16.3) χ2(1) =11.0 <0.01 30. Event happened to your close one, you didn’t see or experience, still be disturbed 44 (10) 33 (18.3) χ2(1) =8.2 <0.01
Chapter 8:Cross-cultural comparisons: Results of Study 3 123 attacked by a known person (χ2(1) =63.2, p<0.05). Finally, they were also more likely to report being forced to have sex when they were less than 16 years old (χ2(1)
=20.3, p<0.05), being physical attacked (χ2(1) =63.2, p<0.05), being sexually harassed at work or school (χ2(1) =20.8, p<0.05), being forced to be touched or touching someone in a sexual way either when they were younger than 16 (χ2(1)
=65.8, p<0.05) or16 years or older (χ2(1) =12.3, p<0.05), and being disturbed by something not happening to themselves but to their close ones (χ2(1) =8.2, p<0.05).
8.3 COMPARISIONS OF MODIFIABLE LIFESTYLE FACTORS
The comparisons of modifiable lifestyle factors among older women in
Vietnam and Australia are presented in Table 8.3. Vietnamese women and
Australian women had different modifiable lifestyle factors, including vegetable consumption, fruit consumption, tobacco smoking habits, physical activity levels, exercise, sleeping habits, and BMI (p<0.05). The Australian women were twice more likely to have 5 serves of vegetables and 2 serves of fruit daily than women in
Vietnam (p<.05). Many Australian women drank alcohol (83.1%, n=147), smoked tobacco (32.0%, n=57) and had more than 3 cups of caffeine daily (91.5%, n=161).
In contrast, very small numbers of Vietnamese women had these habits ((9.8%, n=43; 1.4%, n=6; and 8.4%, n=37, respectively). More than 10% of Vietnamese participants (11.4%, n=50) reported sedentary lifestyles. This number was only 2.2%
(n=4) among Australian women. Compared with 9.3% (n=15) of women in Australia who had sleeping problems, the prevalence of sleep disturbance was four times higher among women in Vietnam (39.6%, n=174). The number of obese women in
Australia was ten times higher than it was in Vietnam (40.2%, n=74 vs 4.1%, n=18).
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Table 8.3: Modifiable lifestyle characteristics among older women in Vietnam (n=440) and Australia (n=184) In In Modifiable lifestyle factors Differences p level Vietnam Australia n (%) n(%) Overall physical activity 5 (0-10) 6 (0-10) z=-5.29 <0.01 (Median [range]) Having at least of 5 serves of 171(38.9) 134 (72.8) χ2(1) =59.89 <0.01 vegetable daily ≥ 6 months Having at least 2 serves of 167(38.0) 142 (77.2) χ2(1) =79.83 <0.01 fruit daily ≥ 6 months Having more than 3 cups of 37 (8.4) 161 (91.5) χ2(1) =397.72 <0.01 caffeine daily Alcohol drinking Never 397(90.2) 30 (16.9) χ2(3) =341.62 <0.01 In the past 15 (3.4) 9 (5.1) Occasionally 24 (5.5) 95 (53.7) Regularly 4 (0.9) 43 (24.3) Smoking χ2(2) =131.17 <0.01 Non-smoker (98.6) (68.0) Smoker in the past (0.7) (25.3) Current smoking (0.7) (6.7) <0.01 Daily physical activity level χ2(3) =22.16 Very active 64 (14.5) 16 (8.9) Moderately active 216(49.1) 118 (65.9) Mildly active 110(25.0) 41 (22.3) Sedentary 50 (11.4) 4 (2.2) Number of times exercised in the past month 282 (64.1) 41 (22.9) χ2(4) =247.26 <0.01 None 13 (3.0) 48 (26.8) 1-2 a week 8 (1.8) 45 (25.1) 3-4 a week 6 (1.4) 23 (12.8) 5-6 a week 131(29.8) 22 (12.3) Daily Sleep disturbance 174(39.6) 15(9.3) χ2(1) =50.2 <0.01 BMI Underweight 2 (11.0) 33 (7.5) χ2(3) =156.74 <0.01 Normal 57 (31.0) 295 (67.0) Overweight 46 (25.0) 94 (21.4) Obese 74 (40.2) 18 (4.1)
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8.4 COMPARISONS OF DEPRESSIVE SYMPTOMS, HEALTH- RELATED QUALITY OF LIFE, AND CHRONIC DISEASE
Detailed comparisons of depressive symptoms, HRQOL, and chronic disease among the older women in Vietnam and in Australia are presented in Table 6.4.
Overall, prevalence of stroke, T2DM, arthritis, and osteoporosis were similar between the women in Vietnam and Australia (p<0.05). Apart from that, women in
Australia had better physical health (p<0.05); and women in Vietnam had better self- reported mental health (p<0.05), but they also had more chronic conditions (p<0.05).
The prevalence of high blood pressure (χ2(1) =20.9, p< 0.05), and coronary heart disease (χ2(1) =56.9, p< 0.05) among the women in Vietnam were higher than among the women in Australia. The prevalence of breast cancer (χ2(1) =8.4, p< 0.05) among the women in Australia was higher than among women in Vietnam. Even though the numbers of women who had depressive symptoms in Australia and in
Vietnam were similar, the prevalence of major depression in Vietnam was almost eight times higher than it was among women in Australia (χ2(5) =285.6, p< 0.05).
8.5 MODEL COMPARISONS
Study 2 tested the model describing the influence of the number and impact of SLEs, and perceived stress on modifiable lifestyle factors, depressive symptoms,
HRQOL and chronic disease among older women in Vietnam. The study included perceived stress and social support as predictor variables. These data had not been collected in the Australian dataset. Therefore, to be comparative, in the modelling, data about perceived stress and social support were not included. Also, data about vegetable, fruit and tobacco consumption in the Australian dataset had not been collected as a continuous variable, as they were in the Vietnamese dataset.
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Table 8.4: Depressive symptoms, HRQOL, and chronic disease among older women in Vietnam (n=440) and Australia (n=184)
In Vietnam In Australia p Differences n (%) n (%) level Physical health 34.32 50.46 z=-8.98 <0.01 median (range) (10.37-61.81) (17.13 - 61.19)
Mental health 59.52 57.16 z=-3.49 <0.01 median (range) (17.13-69.77) (20.18 - 68.13)
Chronic conditions 2 (0-6) 1 (0-5) z=-5.53 <0.01 median (range)
Hypertension 239 (54.3) 61 (34.1) χ2(1) =20.9 <0.01
Coronary heart disease 123 (28.0) 2 (1.1) χ2(1) =56.9 <0.01
Stroke 18 (4.1) 2 (1.1) χ2(1) =3.6 0.08
Type 2 diabetes 57 (13.0) 15 (8.4) χ2(1) =2.59 0.11
Breast cancer 2 (0.5) 6 (3.4) χ2(1) =8.4 <0.01
Arthritis 73 (40.8) 213 (48.4) χ2(1) =3.0 0.09
Osteoporosis 34 (19.0) 72 (16.4) χ2(1) =0.6 0.48
Depression
No 332 (75.5) 122 (72.2) χ2(5) =285.6 <0.01
Mild 68 (15.5) 45 (26.6)
Major 40 (9.0) 2 (1.2)
Since the Structural Equation Modelling data analysis using AMOS requires continuous variables, these variables were also removed from the modelling.
First, Study 3 re-ran the model describing the influence of the number and impact of stressful life events on modifiable lifestyle factors, depressive symptoms,
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HRQOL and chronic disease among older women in Vietnam. In this modelling, data about perceived stress, social support, and vegetable, fruit and tobacco consumption were not included. Then, Study 3 modelled the influence of the number and impact of stressful life events on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Australia. In this modelling, the number of SLEs, SLE impact in the previous year, average number of alcohol drinks per day, average number of caffeine drinks per day, BMI, sleeping disturbance, depressive symptoms, HRQOL, and number of chronic diseases were included as variables.
The model, which was developed based on Schwarzer and Schulz’s conceptual model (Schwarzer & Schulz, 2002) (see Figure 8.1), was used as a preliminary study framework to explore how and to what extent the number and impact of SLEs influenced modifiable lifestyle factors, depressive symptoms,
HRQOL and chronic disease among older women in both Vietnam and in Australia.
The preliminary study framework hypothesised that exposure to SLEs would develop or reinforce health-compromising behaviours such as excess alcohol drinking
(Krueger et al., 2011; Slopen et al., 2011), sedentary lifestyle (Krueger et al., 2011;
Mainous et al., 2010), sleep deprivation (Ware et al., 1996), and elevated BMI (Barry
& Petry, 2008). With these health-compromising behaviours, people would experience reduced HRQOL (Lau, 2013; Renzaho et al., 2013; Staniute et al., 2013;
Takei et al., 2012) and become more likely to have chronic illness (Pyykkönen et al.,
2010; Renzaho et al., 2013; Segerstrom & O’Connor, 2012). In addition, the study also hypothesised that people exposed to SLEs would be more likely to develop depression (Lee et al., 2013; J. I. Manuel et al., 2012; Renzaho et al., 2013) and this would lead them to report decreased HRQOL and more chronic conditions (Bajor et al., 2013).
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For both the Vietnamese dataset and the Australian dataset, Study 3 applied the same approach as Study 2 to model the influence of the number and impact of
SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women. First, a binary correlation analysis was undertaken to examine the associations among the variables in the preliminary study framework.
Again, as the continuous variables in the preliminary study framework were not normally distributed, the Spearman rho test was used to examine the correlation between two continuous variables. Based on findings of the binary correlation analysis, the preliminary study framework was modified and finalised. The final hypothesised model, rather than the preliminary study framework, was tested to identify whether the model fit with the study data using Structural Equation
Modelling statistical analysis method (SEM).
Prior to the test, the assumptions of SEM were examined. This statistical method assumes the continuous variables are normally distributed, and there are no missing data or outliers. As the Vietnamese dataset had a few data missing at random, the data were then imputed using the expectation maximisation functions in
SPSS. In the Australian dataset, there were five women with a lot of missing data.
These women were excluded from the data analysis. Among the remaining 179 participants, there was little missing data at random so these missing data were then imputed using the expectation maximisation functions in SPSS. Also, since the assumption of normal distribution in SEM was violated in both datasets, the ADF and the Bollen-Stine bootstrap p function were used to adjust chi-square for non- normality in AMOS when running SEM to test the goodness of fit between the final hypothesised model and the data.
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Figure 8.1: Preliminary study framework about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and in Australia
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8.5.1 The influence of SLEs on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Vietnam As discussed, this section remodelled the influence of the number and impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam and presents findings from the test of the goodness of fit between the hypothesised model and the Vietnamese data. Table 5.7 presented findings on the associations among the variables in the Vietnamese dataset.
Based on this table, non-significant correlations were removed from the preliminary study framework (Figure 8.1), including: the paths between number of SLEs and number of alcohol drinks per day and BMI; the paths between impact of SLEs in the previous month and overall physical activity levels and BMI; the paths between alcohol drinks per day and physical health; the paths between mental health and number of chronic diseases; the paths between overall physical activity level and mental health; and the paths between BMI and physical and mental health. The following significant correlations were added in the preliminary study framework: the paths between the number of SLEs; SLE impact in the previous year; and physical health, mental health, and number of chronic diseases. This addition allowed the study to investigate the direct influence of the number of SLEs, SLE impact in the previous year and perceived stress on physical health, mental health, and the number of chronic diseases. The preliminary framework after these modifications became the final hypothesis model (Figure 8.2). This final hypothesised model was tested to identify whether the model fitted with the study data among older women in Vietnam. Then, SEM was conducted to test the goodness of fit between the hypothesised model and the study data and it was found that the
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Figure 8.2: Final hypothesised model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam
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hypothesised model did not fit the study data and model modification was needed to achieve a good fit. The modifications done were not only based on statistical findings including the modification indices and the coefficient results of the paths, they were also theoretically reasonable. After modification, the modified model was re-tested for good fitness. Figure 8.3 presents the final model describing the influence of the number and impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam.
The figure also displays standardised path coefficients of the modified model. All paths were significant at p < 0.05. The model was fit with (1) p<0.24; (2)
χ2/df=1.22; (3) RMSEA=0.02; PCLOSE =0.94; GFI=0.99; Adjusted GFI=0.98;
SRMR=0.04. These indicators of the test of fit above indicated that the modified model fit the observed data.
The figure shows that among older women in Vietnam, the number of SLEs indirectly influenced physical health, mental health and the number of chronic diseases through increasing overall physical activity levels (β =0.10, p<0.05) and developing depressive symptoms (β =0.12, p<0.05). The impact of SLEs in the previous year directly decreased mental health (β =-0.17, p<0.05). The impact of
SLEs in the previous year also indirectly impacted physical health, mental health and the number of chronic diseases through increasing sleeping disturbance (β =0.19, p<0.05), and developing depressive symptoms (β =0.34, p<0.05). Figure 8.3 also indicated that an increase in level of overall physical activity levels would increase physical health (β =0.29, p<0.05) and decrease risk of chronic disease (β =-0.17, p<0.05). An increase in sleep disturbance would increase the number of chronic diseases (β =0.17, p<0.05) and decrease physical health (β =-0.30, p<0.05) and mental health (β =-0.15, p<0.05).
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Figure 8.3: Final model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam with standardised estimates (n=440)
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An increase in BMI was associated with an increase in the number of chronic diseases (β
=0.29, p<0.05). Finally, the figure indicated that an increase in depressive symptoms would increase risk for chronic disease (β =0.18 p<0.05) and decrease general health in terms of both physical (β =-0.30, p<0.05) and mental health (β =-0.16, p<0.05).
8.5.2 The influence of stressful life events on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Australia This section reports on the procedure to model the influence of the number and impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam to the Australian dataset. First, binary correlations among the variables were examined. This step aimed to finalise the hypothesised model. As the continuous variables were not normally distributed, the Spearman rho was used to examine their binary associations. The level of significance was set at α=0.05. Table 8.5 shows the binary correlation among the study variables in the Australian dataset. Overall, the table indicates that there were significant correlations between numbers of SLEs and depression.
Impact of SLEs in the previous year correlated with BMI. The table also shows the associations between: overall physical activity level and physical health; BMI and physical health and number of chronic diseases; sleep disturbance and physical and mental health; and depressive symptoms and physical health, mental health, and numbers of chronic diseases.
Based on the findings presented in the Table 8.5, several non-significant paths were removed from the preliminary framework (Figure 8.1), including: the pathways between the number of SLEs and average number of alcohol drinks, overall physical activity levels, BMI, and sleep disturbance; the pathways between SLEs’ impact in the previous year and average number of alcohol drinks, overall physical activity levels, sleep disturbance, depressive symptoms; the pathways between alcohol consumption and physical health, mental health
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Table 8.5: Correlation matrix among variables in Australian dataset (n=184)
1 2 3 4 5 6 7 8 9 10
1. Number of stressful life events -
2. Impact of SLEs last year .163*
3. Alcohol drink -.114 -.053
4. Overall physical activity -.103 -.081 .081
5. BMI .067 .197** -.037 -.480**
6. Sleep disturbance .123 -.076 -.008 -.336** .097
7. Depressive symptoms .246** .063 -.116 -.214** .115 .495**
8. Physical health .006 -.055 .130 .503** -.362** -.320** -.147*
9. Mental health -.100 -.151* -.093 -.017 .075 -.253** -.258** -.169*
10. Number of chronic diseases .040 .080 .006 -.124 .249** .081 .159* -.316** .144 -
**. Correlation is significant at the .01 level (2-tailed) *. Correlation is significant at the .05 level (2-tailed)
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Figure 8.4: The final hypothesised model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, health-related quality of life, and chronic disease among older women in Australia
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number of chronic diseases; the pathway between overall physical activity level and mental
health; the pathway between overall physical activity level and number of chronic diseases; the pathways between BMI and mental health; and the pathways between sleep disturbance and number of chronic diseases.
A significant path between SLE impact in the previous year and mental health was
added to the preliminary study framework (Figure 8.1). This addition allowed the study to
investigate the direct influence of the SLE impact in the previous year on mental health. The
preliminary framework after these modifications became the final hypothesised model
(Figure 6.4). The final hypothesised model, rather than the preliminary study framework, was
tested to identify whether the model fit with the study data using the SEM.
Then, SEM was conducted to test the goodness of fit between the hypothesised model and the
study data and it was found that the hypothesised model did not fit the study data and model
modification was needed to achieve a good fit. The modifications done were not only based
on statistical findings, including the modification indices and the coefficient results of the
paths, but were also theoretically reasonable. After modifying, the re-modified model was re-
tested for good fitness. The results from testing the goodness of fit between the modified
model and the Australian data are presented in Figure 8.5. The figure displays standardised
path coefficients of the modified model. All paths were significant at p < 0.05. The model
was fit with (1) p=0.19; (2) χ2/df=1.25; (3) RMSEA=0.04; PCLOSE =0.67; GFI=0.96;
Adjusted GFI=0.93. Figure 8.5 presents the final model describing the influence of the
number and impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL
and chronic disease among older women in Vietnam. These indicators of the test of fit above
indicated that the modified model fit the observed data.
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Figure 8.5: Final model about the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Australia with standardized estimates (n=184)
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Figure 8.5 indicates that among older women in Australia, the number of
SLEs indirectly influenced mental health through increasing depressive symptom (β
=0.21, p<0.05); the SLEs’ impact in the previous year directly influenced mental health (β =-0.23, p<0.05). The figure also indicated that overall activity level positively influenced physical health (β =0.44, p<0.05); an increase in BMI increased the number of chronic diseases (β =-0.23, p<0.05); sleep disturbance negatively influenced both physical (β =-0.22, p<0.05) and mental health (β =-0.18, p<0.05), but was positively associated with depressive symptoms (β =0.51, p<0.05). Finally, the figure shows that an increase in depressive symptoms decreased mental health (β =-
0.26, p<0.05).
8.6 SUMMARY OF THE FINDINGS OF STUDY 3
Study 3 compared SLEs, modifiable lifestyle factors, depressive symptoms,
HRQOL, and chronic disease among older women in Vietnam and in Australia. The study found that the Australian and Vietnamese older women experienced a similar number of SLEs and a number of older women had depressive symptoms, prevalence of stroke, T2DM, arthritis, and osteoporosis. Apart from that, the Vietnamese women were more likely to experience serious disaster, jail, serious money problems, losing a baby, physical attack by known person, and being forced to have sex as an adult.
The Australian older women were more likely to experience seeing serious accidents or domestic violence, parents’ or their own separation or divorce, caring for a handicapped person, sudden death of a close person, being forced to have sexual relations in childhood, sexual harassment at work or school and being forced to be touched or touch someone in a sexual way. Australian older women were also more likely to be disturbed by something not happening to themselves but to people close to them. The Australian older women were also more likely to report following
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healthy diet recommendations. They were also more likely to consume alcohol and caffeine drinks, and to smoke tobacco. Vietnamese older women were more likely to report sedentary lifestyles and sleeping problems. The number of obese older women in Australia was ten times higher than it was in Vietnam. Older women in Vietnam had more chronic conditions. The prevalence of high blood pressure and coronary heart disease among older women in Vietnam was higher than it was in Australia.
The prevalence of major depression in Vietnam was almost eight times higher than in
Australia. The prevalence of breast cancer among older women in Australia was higher than it was among older women in Vietnam.
The study also compared the models describing the influence of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and in Australia. Findings from the study supported the theory to a certain extent. Among Vietnamese women, the number of SLEs indirectly influenced physical health, mental health and number of chronic diseases through increasing overall physical activity levels (β =0.10, p<0.05), and developing depressive symptoms (β =0.12, p<0.05). The impact of SLEs in the previous year directly decreased mental health (β =-0.17, p<0.05) and also indirectly influenced physical health, mental health and number of chronic diseases through increasing sleeping disturbance (β =0.19, p<0.05), and developing depressive symptoms (β
=0.34, p<0.05). Whereas among Australian women, the number of SLEs indirectly influenced mental health through increasing depressive symptom (β =0.21, p<0.05); the SLE’s impact in the previous year directly influenced mental health (β =-0.23, p<0.05). So far, Chapters 4, 6, and 8 have presented findings in Studies 1, 2, and 3.
The next chapter will discuss these findings.
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Chapter 9: Discussion and conclusion
This research was undertaken to understand the stressful life events (SLEs), perceived stress, social support, modifiable lifestyle factors (vegetable and fruit consumption, smoking, alcohol drinking, physical activity, exercise, sleep problems, and BMI), depressive symptoms, HRQOL and chronic diseases among older women in Vietnam. The study also explored the influence of SLEs and perceived stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic diseases in this population. Moreover, the research investigated the roles of perceived stress and social support on the relationship between SLEs and health. Finally, the research compared findings about demographic characteristics, SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease from a Vietnamese dataset with those from an Australian dataset.
The research had three studies: (1) a pilot study, which translated the valid
English instruments into Vietnamese and assessed the translation equivalence, face validity, study feasibility, internal consistency, and test retest reliability of the
Vietnamese versions of the research instruments; (2) a main survey, which explored
SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL, and the number of chronic diseases among older women in
Vietnam; and (3) the cross-cultural comparisons of SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and the number of chronic diseases among older women in Vietnam and Australia.
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Chapter 9 presents a discussion of the research findings. The chapter has seven sections. First is a discussion about the Vietnamese versions of the research instruments. Second is a comparison of the results in terms of demographic characteristics, SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic diseases. Third is a discussion about the model describing the impact of
SLEs on health. Fourth is discussion about perceived stress and social support and their roles in the relationship between SLEs and health among Vietnamese older women. Fifth is a discussion about the study’s strengths and limitations. Sixth is a discussion about recommendations for future practice and research. Finally, the chapter presents a conclusion to the research.
9.1 THE VIETNAMESE VERSIONS OF THE RESEARCH INSTRUMENTS As there was a lack of valid Vietnamese research instruments to measure the variables of interest, Study 1 commenced with using standard translation and back translation processes to translate available valid English instruments into
Vietnamese. As seen in Chapter 4, Study 1 revealed that (1) the Vietnamese versions of the instruments kept the same meaning as the English versions of the instruments, and (2) the language used in the Vietnamese versions of the instruments was clear for
Vietnamese older women. This shows the good translation equivalence and face validity of the Vietnamese versions of the instruments.
As the research instruments were originally developed in Western cultures, it would have been better if the Vietnamese versions of the instruments had been modified for Vietnamese culture prior to data collection in the Vietnamese population. However, this step was not conducted in Study 1 for a number of reasons. First, two of the instruments (CED-S for depression symptoms and SF-12)
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have been previously used in a Vietnamese population and the other study measurement instruments had been previously used in various populations, including
Asians, who have similar cultures to Vietnamese. It was assumed that these measurements would still have similar content validity for Vietnamese people.
Second, the resources for this study – for example, time and funding – were limited, and therefore the researcher placed priority on the main scope of the research.
Before further discussing psychometric results, it was noted that the reported information about average income of the Vietnamese older women was different at the two time points in Study 1. Compared to the reported information in Time 1, the participants reported a higher income in Time 2 (see Table 2.1). This is understandable in Vietnamese context as at Time 1 the participants had not been familiar with the researchers and they may have felt uncomfortable to disclose their income status. However, at Time 2, they may have felt more comfortable to indicate their income and change the answers about their income.
Based on Kline's criterion (2005), the internal consistency reliability data
(presented in Table 4.2) indicated that all reliability coefficients passed Kline's criterion for internal consistency (≥ 0.7), except for the internal consistency reliability of the Vietnamese version of the LSC-r, which was a little below the desirable value (0.67 vs 0.70). Compared with the internal consistency reliabilities found in previous studies, the alpha coefficients of the Vietnamese versions of the study instruments were comparable (Lee, 1992, 2012; Wolfe & Kimerling, 1997). To be specific, the alpha coefficient of the Vietnamese version of PSS-10 was 0.80 while it ranged from 0.67-0.91 in previous populations (Lee, 2012). The internal consistency of the General Sleeping Disturbance Scale, which was 0.81, is also
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comparable with 0.82 in other previous studies (Lee, 1992). The internal consistency reliability of the LSC-r was slightly below the desirable value (.70), but still comparable with a previous study’s finding (0.67 vs 0.73) (Wolfe & Kimerling,
1997). As Study 1 was conducted in a small sample size (n=31), a slightly low
Cronbach’s alpha of this sole instrument was still considered to be acceptable.
As seen in Table 4.3, all of test-retest reliability data passed the criterion for test-retest (≥ 0.5), except for the physical health component of SF-12 which was a little below the desirable value (0.41 vs 0.50). In fact, the test-retest reliability coefficient of the Vietnamese version of the CES-D Scale were even better than it was in previous studies (0.86 vs 0.51-0.67 (Radloff, 1977)). The test-retest correlation coefficient of the MOS social support survey was slightly lower than it was in a previous study (0.59 vs 0.72). This could be due to the small sample size of the study. Another possible explanation is that the family might change their support to the participants when the research investigation began. Yet, a previous study found that test-retest correlation of PCS and MCS was 0.89 and 0.76 respectively
(Ware et al., 1996). The current study found that test-retest correlation of PCS and
MCS was 0.41 and 0.84 respectively. Compared to the desirable criteria, the
Vietnamese version of the physical component of SF-12 was slightly below the desirable value (0.41 vs 0.50). As chronic disease was common among the participants, discomfort or pain related to chronic disease may have fluctuated over the month and this could have influenced the consistency in self-report of physical health over the month (Dominick, Ahern, Gold, & Heller, 2004). Therefore, the physical component of the SF-12 scale was still considered appropriate to be used in
Study 2.
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Findings about the translation equivalence, face validity, internal consistency and test-retest reliability of the Vietnamese versions of the study instruments at a one-month interval suggest that the Vietnamese versions of the research instruments had sufficient translation and face validity, internal consistency and test-retest reliability to measure the study variables among Vietnamese older women. Thus, measurement using these Vietnamese versions of the research instruments was reliable and the results were stable over the month for this group of Vietnamese older women. The Vietnamese versions of the instruments were able to be used to collect data in Vietnamese people. The use of these Vietnamese instruments gave researchers opportunities to gain more knowledge about psychosocial stress, social support, modifiable lifestyle factors, HRQOL, and chronic disease among older women in Vietnam as well as provide a research opportunity to conduct cross- cultural comparisons related to stress and influences of stress.
9.2 THE CROSS-CULTURAL COMPARISONS
The Vietnamese versions of the instruments developed in Study 1 were then used in Study 2 to collect data about SLEs, perceived stress, social support, modifiable lifestyle factors (vegetable and fruit consumption, smoking, alcohol drinking, physical activity, exercise, sleep problems, and BMI), depressive symptoms, HRQOL, and chronic disease among older women in Vietnam. Data from
Study 2 were used to compare with secondary data from Australia in Study 3. This section discusses the results of SLEs, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and
Australia.
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9.2.1 Demographic characteristics
Before discussing the similarities and differences in demographic characteristics between older women in Vietnam and those in Australia, it is worth noting that the Australian dataset is an 11th year follow-up of a longitudinal study conducted on mid-life women, who commenced the study between 45-60 years of age (Xu et al., 2010). The population of this dataset may be younger than the real population of Australian older women aged 60 and over. These may have contributed to the differences; for example, the older people are, the greater their likelihood of being widowed.
Apart from that, there are several possible reasons to explain why Vietnamese older women had lower levels of education and income First, the majority of
Vietnamese women were born into a belief that “one boy can be counted but not ten girls” (nhất nam viết hữu, thập nữ viết vô) (Phan, 2001). Consequently, among people aged 60 and over, priority for education has been given to males (Bui et al.,
2012). Second, as women frequently had fewer opportunities for higher education, they also had fewer chances for paid employment (Bui et al., 2012). Common occupations for women included housework, gardeners, farmers, or self-vendors.
Working in these occupations, they did not have a retirement fund or pension to rely on when they aged, and so they may be financially dependent on others (Vietnamese
Ministry of Health, 2006). Even for those who worked in government organisations, where people would have pensions as they aged, they still could not receive pensions monthly if they had not contributed to the superannuation for at least 20 years. These possible reasons could account for the fact that older women in Vietnam had low education levels and incomes.
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Concerning marital status, financial dependence and gender expectations can provide potential explanations for the fact that the Vietnamese women were less likely to divorce than those in Australia. First, due to having low personal income, many Vietnamese older women live financially dependently on others. Second, traditionally, Vietnamese women were taught that “women keep home warm” (“đàn bà xây tổ ấm”), and “a good woman has only one man” (gái chính chuyên một chồng) (Phan, 2001). It was also a common belief that “it is your destiny to have a good or bad husband” (“trong nhờ đục chịu”) (Phan, 2001). This implies that (1) women need to self-adjust or suffer to keep the family happy; (2) solely women are blamed for an unhappy family; and (3) divorce should not happen. These social norms have prevented women from withdrawing from their unhappy marriages (Vu et al., 2014). On the other hand, as the Australian women have had higher education levels and better incomes, they appear more financially independent from their husbands and husbands’ families. In a financial crisis, Australians may also be able to receive support from the Government (Lifeline Australia, 2016). In addition, the norm restricting women to have only one husband for their whole life does not exist in Australia. Therefore, a decision to separate and divorce can be made when needed by most Australian women.
In terms of employment, the availability of social systems in Vietnam and
Australia could provide potential explanations of why the Vietnamese older women had similar proportions of employment to those in Australia. At present, many
Vietnamese older people do not have pensions and the social welfare system for older people in Vietnam is still limited (Thông tấn xã Việt Nam, 2016; Vietnamese
Ministry of Health, 2006). Culturally, Vietnamese older people are living in the
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extended family with their children and grandchildren are being taken care of
(Galanti, 2000). However, children, especially those of low economic status, may have not been able to provide economic support for their ageing mothers. The older women may have wanted to support their children by not becoming a burden for them. The Vietnamese older women may have had to work to support themselves during their older years. On the other hand, more women in Australia had pensions.
The social welfare support system has existed in Australia and can provide financial and other support for older women as needed. Thus, Australians did not have to work in their old age to financially support themselves.
9.2.2 Stressful life events
As presented in Chapter 8, Vietnamese and Australian women were exposed to SLEs differently. Prior to discussing the differences, it is worth noting that about two thirds of the Vietnamese data were collected from Dong Thap province, where the majority of residents worked in agriculture. In 1978, this area experienced a serious flood, and as a result, many people living in this area experienced famine and poverty. Therefore, the experiences of disaster and serious money problems could be over reported due to the experiences of this group of women. Also, as the participants in the Vietnamese dataset were older than the Australian dataset, age might be a confounder as age can be associated with higher likelihood of experiencing loss of a close person. Therefore, interpretation of the prevalence of experience with disaster, serious money problems, and experience losing a close person for Vietnamese older women should be viewed with caution.
As potential explanations for Vietnamese older women’s lower prevalence of divorce were discussed in the previous section, this section will not repeat the same
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information. Instead, this section discusses the experience of other SLEs by analysing the differences in history, culture, and social systems that exist in the two nations.
From the historical perspective, several wars occurred between 1930 and
1979 in Vietnam (Vietnamese Embassy Australia, 2013). During the wars, people were likely to have experienced torture, being in jail or having family member(s) in jail. After the wars, there was also a revolution, isolation and embargo from the
United States and Western countries, and a mass flow of refugees (Vietnamese
Embassy Australia, 2013). During this, Vietnamese people lived with very limited economic and medical resources (Witter, 1996). Consequently, the abortion rate in
Vietnam rose rapidly between 1976 and 1987: from 70,281 cases to 811,176 cases
(Goodkind, 1994). Furthermore, many children died because of accidents (Tran,
Luong, & Khieu, 2012; Vietnamese Ministry of Health, 2006). Two thirds of children aged six and younger in low-income family did not receive treatment or treated at home when they were sick (Vietnamese Ministry of Health, 2006). These provide potential explanations why the Vietnamese older women were more likely to report close family members, or their self being in jail and losing a baby or child.
From the cultural perspective, gender roles could account for the difference in exposure to caring for those with serious health problems and witnessing serious accidents among older women in Vietnam and Australia. In Vietnam, people usually stay in the extended family house (Galanti, 2000). In that family, women have responsibility to take care of family members (Galanti, 2000; Knodel, Loi, Jayakody,
& Huy, 2005). Among women aged 60 and over, many have stayed at home and done housework while the men go out to work (Galanti, 2000; Knodel et al., 2005).
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Thus, they were more likely to take care of their relatives but had less chance to experience serious accidents outside of the house context. On the other hand, two thirds of Australian women (77%) lived in a couple family or as couple families with dependent children that lived separately from rather than in an extended family
(Australian Bureau of Statistics, 2016). Thus, they may have less chance to take care of their relatives. Also, gender equity has been advocated in Australia for decades.
Australian women can undertake higher education, and often go out for work or to socialise and so they could have more chance of seeing serious accidents out of the house context. This may explain why, compared to Australia, Vietnam had more women who had experienced caring for those with serious health problems, but had fewer women who had experienced witnessing serious accidents.
Gender roles may also explain why more Vietnamese women had experienced being physically attacked by a known person or being forced to have sex when older than 16 years old than Australians. Traditionally, it is a common belief that “females were born not for their own family, but their husband’s” (nữ sinh ngoại tộc). Vietnamese women were taught to “obey their husbands when they get married” (xuất giá tòng phu) (Schuler et al., 2006), and “when the husbands get angry, wives have to stop talking” (Chồng giận thì vợ bớt lời) (Phan, 2001). This implies that (1) women are expected to live in and work for their husband’s family,
(2) wives are controlled by their husbands, and (3) men’s hot tempers are culturally considered acceptable and women need to adjust themselves to keep the harmony. In this context, more domestic violence against women, including verbal, physical, mental and sexual abuse, may occur. Husbands might have assumed that they have the right to shout or beat their wives as a way to educate or order them, while wives
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may have assumed that they have to suffer to keep the harmony of the family, and have to follow their husband’s orders, including having sex (Ha, 2008). In fact, recent studies have revealed that violence against women in Vietnam is common
(Jonzon, Nguyen-Dang, Ringsberg, & Krantz, 2007; Krantz & Nguyen-Dang, 2009;
Nguyen-Dang & Krantz, 2009; Nguyen-Dang et al., 2009; Nguyen-Dang et al.,
2008), with about 58% of women in Vietnam having suffered at least one form of domestic violence (United Nations Office on Drugs and Crime, 2014).
In regards to violence, social systems, for example education, that exist in
Vietnam and Australia could also explain the findings on violence experiences in addition to gender roles. In Vietnam, as it is commonly believed that violence and sex are very sensitive topics, especially for children, education about violence and sex was not introduced into schools until the late 1990s. This might mean that people have insufficient knowledge to identify cases of sexual abuse and violence that occurred in their early ages. In addition, generally, violence and sex were very limitedly discussed in public in Vietnam. This might also contribute to causing a stigma for people, especially to disclose sexual harassment or abuse in young ages.
On the other hand, violence and sex have been discussed in Australian primary schools (Milton, 2003). This may allow Australians be able to recognise physical violence and sexual abuse in their early lives and be more open to disclose experiences of violence, including sexual harassment or abuse. These issues may explain why Australian women were more likely to report physical attacks and sexual harassment, especially experiences in their young ages. With knowledge of violence, Australian women may also know how to stop violence.
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In addition to education, laws and services to protect victims of violence could also provide potential explanations for the differences of violence experiences among older women in Vietnam and Australia. In Australia, laws and several supporting organisations, which protect people from violence, exist in Australia
(Lifeline Australia, 2016). Australians are also able to access protection from solicitors or police, and get free legal services regarding domestic violence from
Community Legal Centres (Lifeline Australia, 2016). They can also have financial support, free counselling and emergency accommodation from the government
(Lifeline Australia, 2016). These conditions could help Australians to stop domestic violence. This could provide reasons why Australia had fewer women who had experienced physical attacks and sexual abuse when they were 16 and over.
The social welfare system in Australia are not only available for women experiencing domestic violence, but also delivers a range of payments and support services for those in crisis, including those with disability (Australian Department of
Human Services, 2016). Besides government organisations, there are also community, non-government organisations and volunteer groups to help people with disability. This may allow Australians to give more care to those with disability. On the other hand, the current social services for those with disability in Vietnam are still limited (Vietnamese Ministry of Health, 2006). Older women in Vietnam may have interpreted “caring for people with a handicap” means living with them and providing daily care for them and so reported low prevalence of care. Therefore, this difference will need further exploration in future studies.
Among the SLEs researched, as seen in Chapter 6, those that had a high impact on respondents in the previous year included responsibility for taking care of
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other family members, including children with disability, the experience of physical attacks or emotional neglect by people known to them, having a close person die unexpectedly and being in jail. These findings suggest that in the future healthcare professionals need to be aware and provide more support for women who have experienced such events.
Interestingly, for the majority of those who had experienced disasters, money problems, abortion or miscarriage, or having had a close person in jail, they reported no impact of these events during the previous year. There are several possible reasons for this finding. First, the participants were not the ones who experienced being in jail. Second, they may have been exposed to disasters, money problems, abortion or miscarriage a long time ago and the impact of these exposures may have reduced over time. Also, as discussed, Vietnamese older people has gone through wars and loss after wars, so difficult situations such as having close people in jail, lack of healthcare and lack of economic resources happened to many Vietnamese people (Witter, 1996). They might have believed that they were not particular cases from others and they may have normalised the impact of these events. In addition, since many participants lived in the flood zone, an experience of serious floods in the past would not be concerning them anymore. Further, there have been many social and economic improvements in Vietnam in the last two decades and these may have made older women in Vietnam believe that their lives have improved a lot and the impact of these past experiences should be left behind. Thus, Vietnamese women who experienced these SLEs reported no impact in the previous year.
Another interesting finding is that many Vietnamese older women also reported a significant or severe impact from SLEs which had not happened to them,
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but rather to people close to them. An explanation could be that many women in this study stayed at home and took care of their families. They usually had similar family experiences day by day, but were not psychologically prepared to deal with social changes. Listening to the stressful experiences of other people, especially of those close to them, may be a sudden shock but also last for a long time, so that they reported the impact as severe. Another possible explanation is that they might have assumed that they have responsibility to keep the joy for every family member
(Phan, 2001). They might have believed that their responsibility had been not full- filled when those close to them experienced SLEs and they could not help. Also, as the data about SLEs were collected by interviews using self-report questionnaires, the Vietnamese older women might avoid telling their stories. Instead, they may report their own experiences as their close persons’ experiences.
As discussed before, Vietnamese wives commonly have lived with the husbands’ family. Many Vietnamese older women had low education and income.
Generally, they have been staying at home, caring for the housework and family members, and they are financially dependent on others. Vietnamese culture places many gender-based expectations on women, such as having one husband for the whole life, obeying husbands, keeping the harmony for the home, and accepting the hot temper of husbands. The Vietnamese older women have also gone through the wars and life after wars with limited resources. The current support from the
Government for older people is still very limited. Recent research also showed that excess alcohol drinking is a problem among Vietnamese men and domestic violence occurs commonly in Vietnam. Living in this context, older women in Vietnam also
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reported several husband or child-related SLEs, and extended family and war-related
SLEs (as seen in Chapter 6), in addition to the SLEs listed.
Apart from the discussed points, the beliefs about family and family relationships that exist in Vietnam could also provide possible explanations for this finding. In Vietnamese culture, mothers must provide the main care for their children (Knodel et al., 2005) and support their children (Galanti, 2000) even when they are mature. This may make Vietnamese mothers maintain great concerns about their children no matter their children’s age. Yet, as they grow older, supporting their children may not always be possible, especially for those with low income and limited health status. In contrast, they might have needed to be cared for while their children may have had their own lives and worries. In such cases, Vietnamese mothers may have felt they had not fulfilled their responsibilities to their children, even though they had had tried their best. In return, Vietnamese mothers usually expect their children to obey and respect them (Galanti, 2000), and to love their siblings. They may also feel stressed when their children act differently from their expectations.
Findings about the additional SLEs among older women in Vietnam suggest that it is important to ask the older women to endorse all the possible SLEs that happened to them or to their close persons. However, as women may appraise SLEs differently, it is also necessary to consider the role of women’s general stress perceptions when assessing stress among Vietnamese women in conjunction with endorsing the listed SLEs (Lazarus, 1966, 1984, 1990). Also, as exposure to SLEs may lead to adopting an unhealthy lifestyle (Barry & Petry, 2008; Krueger et al.,
2011; Lipsky et al., 2015; Mainous et al., 2010; Slopen et al., 2011; Ware et al.,
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1996), and decrements in health (Blasco-Ros, Herbert, & Martinez, 2014; Kershaw et al., 2014; Verelst, De Schryver, Broekaert, & Derluyn, 2014), findings from this research highlighted a public health concern about modifiable lifestyle factors and health, especially mental health, among a certain number of older women. The next section discusses modifiable lifestyle factors among older women in Vietnam in comparison to Australian older women.
9.2.3 Modifiable lifestyle factors
This research measured modifiable lifestyle factors such as vegetable and fruit consumption, smoking, alcohol drinking, physical activity, exercise, sleep problems, and BMI. With regards to consumption of vegetables and fruit, as seen in
Chapters 6 and 8, the current research found that about two thirds of Vietnamese older women did not have healthy eating and the proportion of older women who had healthy eating in Vietnam was lower than in Australia. Compared to previous data, which showed that 52-88% of Vietnamese women, reported having a recommended diet (Hoang, Ng, et al., 2008; Vietnamese Ministry of Health, 2006), the findings about healthy eating among older women in this research were lower.
A possible explanation is that recently social media in Vietnam have issued several warnings that foods, especially vegetables and fruits, have contained dangerous chemicals (Uga et al., 2009; Vietnamese Ministry of Health, 2006), and so there are potential hesitations for people in Vietnam to eat more of these healthy foods. In addition, many Vietnamese older women had major dental problems
(Vietnamese Ministry of Health, 2006). This may limit the older women in Vietnam from consuming more vegetables and fruits. On the other hand, social media in
Australia clearly spreads information about recommendations for a healthy diet,
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which encourges Australians to have more vegetables and fruit. In terms of self- efficacy, research showed that about 75% of Australians reported moderate to high levels of dietary self-efficacy (Anderson, Anderson, & Hurst, 2010). Dental problems affected a low percentage of Australian elders and this may explain why more Australian women reported having a healthy diet. This may allow the older women in Australia to have more vegetables and fruits. Yet, as the Australian dataset is an 11th year follow-up of a longitudinal study conducted on mid-life women, who commenced the study between 45-60 years of age (Xu et al., 2010), people in this sample may have higher motivation in healthcare than the general Australian older population and so a higher proportion of healthy eating was reported.
With regards to alcohol and tobacco smoking, this research found that a majority of Vietnamese older women did not drink alcohol or smoke, whereas many
Australians reported smoking and drinking alcohol. This finding is in line with previous studies, which showed that the prevalence of alcohol drinking at risk varied from only 0.3-5% in Vietnam (Vietnamese Ministry of Health, 2006). Previous data also showed that 0.2% to 6.0% of Vietnamese women were smoking (Vietnamese
Ministry of Health, 2006); and 0.9% of women aged 65-74 were smoking (Hoang,
Ng, et al., 2008). Previous data has also indicated that among Australian adults,
12.8% are daily smokers (Australian Institute of Health and Welfare, 2016), 88.2% drink alcohol, 20% have more than 2 drinks per day (Australian Institute of Health and Welfare, 2016), and 6%-8% of older women consume alcohol at risk (Australian
Institute of Health and Welfare, 2016).
There are several potential explanations for the differences in alcohol drinking and tobacco smoking among older women in Vietnam and Australia. First,
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generally, Vietnamese people believe that women are not supposed to smoke or drink alcohol (Morrow, Ngoc, Hoang, & Trinh, 2002), though it seems to be acceptable for
Vietnamese women to have a little bit of beer to socialise in a few special events in recent years. Australian women, however, are more involved in different social activities. They are free to drink alcohol or smoke if they want to. These factors may have contributed to the data showing that many Australian women drank alcohol and smoked tobacco.
Poor diet (low fruit and vegetable intake), smoking (Heikkinen et al., 2008;
Holahan et al., 2013; Laaksonen et al., 2006; Minh et al., 2007; Minh et al., 2008;
Shields et al., 2013; Strandberg et al., 2008), excess alcohol use (Hoang, Dao, et al.,
2008; Minh et al., 2008), and excess BMI (Daviglus et al., 2003; Herman et al.,
2012; Hoy et al., 2013; Huang et al., 2006; Pham et al., 2009; Roberts et al., 2003) are associated with decreased general health and an increased number of chronic diseases. Research also indicates that 10 years of cessation would be needed for smokers to have a similar level of HRQOL to those who have never smoked (Shields et al., 2013). Therefore, modifications of these lifestyle factors (eating, smoking and alcohol drinking) are required for better health among older women for both nations.
In terms of physical activity levels and exercise, the current study found that the prevalence of physical inactivity and no exercise was 35.5% and 64.1% respectively in the Vietnamese population, being consistent with Vietnamese national report, which showed that the prevalence of physical inactivity and no exercise in Vietnamese population was reported as 11.0 % - 41.0 % and 35-63% respectively (Vietnamese Ministry of Health, 2006). In detail, the prevalence of sedentary lifestyles among older women in Vietnam was higher (11.4% vs 2.2%)
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than that among Australian women. The Vietnamese older women were also more likely to report no exercise (64.1% vs 22.9%). There are several possible reasons for this. First is that older women in Vietnam had more chronic conditions than those in
Australia. Almost half of the older Vietnamese women had arthritis. Health conditions may have limited Vietnamese older women from undertaking exercise.
Second is a potential belief about physical activity and exercise among older women in Vietnam. Vietnamese older women may have experienced hard work when they were young and they might believe that resting is more important than being active in their older age. Also, more than half of the Vietnamese participants reported at least moderate physical activity. They may believe that they have enough overall physical activity and that exercise is an additional activity to improve health and not normally expected - so it could be skipped. Third is social desirability. As many
Vietnamese do not practice exercise (Vietnamese Ministry of Health, 2006), exercise has not become socially desirable, especially for older women living in rural areas.
Therefore, Vietnamese people may have fewer social expectations regarding exercise. Finally, having available time for exercise is an issue. More than 70% of the older women in Vietnam live in rural areas, and have an education of primary level or less (Vietnamese Ministry of Health, 2006). They might be involved in several forms of house work, including caring for grandchildren (Galanti, 2000), which may not leave them with much time for exercise.
Low physical activity levels are negatively associated with HRQOL (Abell et al., 2005; Gómez et al., 2013; Herman et al., 2012). Even for people with arthritis, increased physical activity levels can increase their HRQOL (Abell et al., 2005) and with people aged 70-80, simply increasing their walking has been shown to improve
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HRQOL (Heesch et al., 2012). Increasing exercise has been shown to be correlated with increased HRQOL (Hassan et al., 2003). Hence, future interventions to reduce sedentary lifestyle and to promote exercise are necessary for older women.
Concerning sleep among older women, Vietnamese women were more likely to have sleep problems than Australians. The prevalence of sleep disturbance among older women in Vietnam was also higher than that reported in a Mexican study
(36%) (Heilemann, Choudhury, Kury, & Lee, 2012). Discomfort associated with chronic disease may also be a potential reason preventing Vietnamese older people from sleeping. In addition, the traditional roles of Vietnamese women in home care
(Knodel et al., 2005) as discussed could also inhibit them from having a good sleep.
Also, as exercise is negatively correlated with sleep disturbance (Yang, Ho, Chen, &
Chien, 2012), lack of exercise frequently can be a reason for the reporting of sleeping problems among Vietnamese older women. These factors can contribute to explaining why older women in Vietnam were more likely to experience sleep problems.
Poor sleep has been linked with a range of health issues (Irwin, 2015), including memory difficulties (Walker & Stickgold, 2005), cognitive decline (Stuart,
2014), increased obesity risk (Kubo et al., 2011), impaired immune function
(Bollinger et al., 2009), susceptibility to infectious and inflammatory diseases
(Vgontzas et al., 2013), hypertension (Cappuccio et al., 2011; Palagini et al., 2013;
Wang et al., 2012), cardiovascular disease (Azevedo et al., 2014; Cappuccio et al.,
2011), stroke (von Ruesten, Weikert, Fietze, & Boeing, 2012), diabetes (Cappuccio et al., 2010), cancer (Luo et al., 2013; Parent et al., 2012; Zhang et al., 2013), and depression (Baglioni et al., 2011; Stuart, 2014). Poor sleep is linked to poor health
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and well-being (Strine & Chapman, 2005). The high prevalence of sleep disturbance among older women in Vietnam raises a concern about health and well-being among this group of women. This finding also suggests that further investigation of the correlates of sleep disturbance would be beneficial to yield suggestions for improving sleep for older women in Vietnam in the future. Yet, Vietnamese people generally believe that for older people, it is normal to experience some sleep problems. To promote their general health and decrease the incidence of sleep disturbance, more campaigns to raise the awareness of sleep problems should be conducted.
With regards to BMI, aaccording to a WHO report, the prevalence of overweight and obesity worldwide is more than 35% for adults, with women more likely to be overweight and obese than their male counterpart (Mitchell & Shaw,
2015). The Americas represents the highest prevalence (62%). The prevalence of overweight and obese women was 26% in Southeast Asia (Mitchell & Shaw, 2015).
A study of 14,220 Taiwanese people found that prevalence of underweight, normal weight, overweight; and obese were 7%, 66%, 23%, and 4%, respectively (Huang et al., 2006). Previous studies showed that more than 13% to 31.2% of Vietnamese women aged 65-74 were overweight and 1.3-2.6% were obese (Walls et al., 2009). A survey of 1407 Vietnamese people aged 20-60 found that the prevalence of overweight and obesity was 33.6% among Vietnamese women (Cuong et al., 2007).
Compared to previous data, the prevalence of overweight and obese women in
Vietnam (25.5%) was comparable to that of Taiwanese people (Huang et al., 2006) and previous studies (Walls et al., 2009), but slightly lower than previous studies’ findings which were conducted on Vietnamese people (Cuong et al., 2007). On the
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other hand, findings from this study about the prevalence of overweight and obese women in Australia (40%) were higher than worldwide prevalence but lower than that of Americans, and a previous report (Australian Institute of Health and Welfare,
2016). In Australia, it was reported that about 74.7% of people aged 65-74 were overweight or obese (Australian Institute of Health and Welfare, 2016). Australia appeared to have more women with excess weight than Vietnam. There are a number of potential explanations for this finding. First, the survey of 1407 Vietnamese people had younger participants (women aged 20-60). The ecomonics has grown in
Vietnam in recent decades. Fast foods with high calories, which have recently arrived in Vietnam, have usually been taken up by the younger generation and were not usually chosen by older people. This may increase the likelihood for younger people to be overweight or obese. In contrast, the fast food industry has been popular in Australia for several years. Many Australians might regularly consume high energy junk food. Yet, participants in the Australian dataset in 2012 were aged 45-
60 and had participated in a longitudinal health research and follow-up for more than
10 years. Hence, they may have placed more concern on healthcare and weight control. These reasons cold explain why Australia had more overweight or obese women than Vietnam. Excess weight is associated with decreased physical health
(Herman et al., 2012; Huang et al., 2006), HRQOL (Hassan et al., 2003; Herman et al., 2012), and associated with chronic disease (Roberts et al., 2003). Therefore, weight control should be a priority for those who are overweight and obese in both nations.
9.2.4 Depressive symptoms, health-related quality of life, and chronic disease
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As seen in Chapter 8, the prevalence of older women who had depressive symptoms was similar in Vietnam and Australia. However, the prevalence of major depression in Vietnam was almost eight times higher than it was among older women in Australia. This finding is interesting as about a decade ago, only 1.2% of the
Vietnamese older population had depression (Ministry of Health, 2003). Even though the depression scale used in this study is not a diagnostic scale, this finding suggests that many older women in Vietnam may suffer from depression without diagnosis and treatment.
There are a number of possible explanations for the difference in findings about depressive symptoms among older women in Vietnam in comparison to
Australians. One of the reasons is primary mental health services availability. In
Australia, mental health has been raised as a concern for healthcare professionals and communities in Australia for decades. Consequently, professional psychological counsellors are available to provide primary mental health care and Australians who have stress or mild depression can access professional psychological help at early stages. On the other hand, in Vietnam, current healthcare services are generally focussed on caring for physical disorders; much less attention has been placed on mental health care. As a result, people in Vietnam may not recognise that they are stressed or depressed. There are no primary professional psychological services, so
Vietnamese who have stress or mild depression cannot access professional psychological help at early stages. Another possible explanation of why Vietnam has higher numbers of older women with major depressive symptoms than Australia is social stigma. In Vietnam, mental health problems are treated in mental health tertiary hospitals, which have mostly taken care of people with serious mental
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disorders. This may have contributed to Vietnamese people believing that their
“sadness” was not too “serious” to require professional mental health care, and stress and mild depression may have developed into major depression as a result of no appropriate mental health care being accessible.
Currently, Vietnamese people mostly have focused on physical health conditions and much less concern has been placed on mental health care. This finding suggests that depression among older women in Vietnam should be a serious concern for healthcare professionals in the future. Further research about depression among older women in Vietnam is needed. Clinical assessments would be useful to detect depression and early treatment is necessary to manage depression among older women. Also, primary mental healthcare and psychosocial counselling services are also required in Vietnam. Future research about the sigma of accessing mental health care services might be useful to promote the use of primary mental healthcare in the community as well.
Concerning chronic disease, the research found that the older women in
Vietnam reported more chronic conditions. Possible explanations for this could be participants’ age. The participants in the Vietnamese sample were older than those in Australia. The number of chronic conditions increases with age. Also, along with the economic growth in Vietnam, eating (Nguyen & Popkin, 2004) and physical activity habits (Au et al., 2012) have changed and the prevalence of overweight and obesity (Pham et al., 2009; Walls et al., 2009) have increased, which has increased the prevalence of chronic disease (Hoy et al., 2013). These factors could be the reasons for increased prevalence of heart disease, stroke, breast cancer and the number of chronic conditions among older women in Vietnam.
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In detail, the prevalence of T2DM, arthritis, osteoporosis and stroke were similar between the women in Vietnam and in Australia. Comparable results were also found for T2DM, with 13% vs 15% (International Diabetes Federation, 2014), arthritis, and osteoporosis, with 48.4% and 16.4% vs 33.9% and 10.4% respectively
(Ministry of Health, 2003), or 39-43% for both (Mwangi et al., 2015). Yet, while a previous study found that 0.4% of women had suffered a stroke (Hoang, Ng, et al.,
2008), findings from this study were higher (4.1% for stroke). Previous data were collected from younger participants (Nguyen et al., 2013). The current study used random sampling and had strong support from the community so that it was able to involve participants from a wide age range (60-94 years old). As ageing is associated with stroke, the higher prevalence of stroke found in this study is expected.
The research also found that the prevalence of hypertension in this study
(54.3%, n=239) is consistent with previous data, which showed that among the older population in Vietnam, 15.3% -50.7% were reported to have hypertension (Hoang,
Dao, et al., 2008; Minh et al., 2007; Pham et al., 2009; Pham et al., 2012). Yet, while a previous study found that 11.9% of women had heart disease (Hoang, Dao, et al.,
2008), findings from this study were higher (28%). As discussed, the previous data were collected from younger participants (Nguyen et al., 2013). The current study used random sampling and had strong support from the community so that it was able to involve participants from a wide age range (60-94 years old). While ageing is associated with heart disease, this increased prevalence of heart disease is also expected.
Compared to Australians, the prevalence of high blood pressure, and coronary heart disease were higher among the women in Vietnam. This finding could be
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explained by eating habits. The Vietnamese older people also generally have a habit of consuming salty food (World Health Organization, 2016b). On average,
Vietnamese people consumed two times higher than the recommended amount of salt
(World Health Organization, 2016b). These could increase their likelihood to have hypertension and heart disease (Meneton, Jeunemaitre, de Wardener, & MacGregor,
2005).
In regards to breast cancer, while a previous study found that 0.28 in 100,000
Vietnamese women had breast cancer (Nguyen et al., 2013), this study found a higher prevalence (0.5% for breast cancer). Apart from the age of the study participants, more emphasis on breast cancer screening among Vietnamese women could be an explanation for this increase.
Prior to discussing the difference in prevalence of breast cancer among older women in Vietnam, it is important to note that breast cancer screening is common for
Australian women aged 40 and over, while it is not a common habit among
Vietnamese women. This higher prevalence of breast cancer among older women in
Australia might be a result of early detection. Apart from this, there are a number of possible reasons why the prevalence of breast cancer was higher among women in
Australia. First, Australians had more risks to develop cancer. Many Australian women had excess BMI and drank alcohol. These lifestyle factors are identified risk factors for breast cancer (Bianchini, Kaaks, & Vainio, 2002). Second, breast-feeding practices differ between the two countries. Research found that breast feeding is a protective factor for breast cancer (Kotsopoulos et al., 2012). Compared to Vietnam, the prevalence of breast feeding was lower in Australia. Indeed, the prevalence of breast feeding in Vietnam was 83.6 - 98.3% (Duong, Binns, & Lee, 2004; L. Li, Thi
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Phuong Lan, Hoa, & Ushijima, 2002), while it was about 69% among Australian women (Australian Institute of Health and Welfare, 2011a). These factors may explain why Australian women were more likely to have breast cancer.
All findings together about chronic disease among older women in Vietnam suggest that chronic disease should be a concern and suggests that there is an increasing need to enhance healthcare services for chronic diseases and to promote general health for Vietnamese older women. The findings about chronic disease among older women in Vietnam and Australia could also explain why older women in Vietnam self-reported much lower physical health than those in Australia.
9.3 THE INFLUENCE OF STRESSFUL LIFE EVENTS ON MODIFIABLE LIFESTYLE FACTORS, DEPRESSIVE SYMPTOMS, HEALTH-RELATED QUALITY OF LIFE, AND CHRONIC DISEASES AMONG OLDER WOMEN IN VIETNAM AND AUSTRALIA Study 2 used SEM to explore the direct and indirect influence of the number and impact of stressful life events and perceived stress on modifiable lifestyle factors, HRQOL and number of chronic diseases among older women in Vietnam.
As reported in Chapter 6, Study 2 found that a number of SLEs indirectly increased physical health through increasing overall physical activity levels. The impact of
SLEs in the previous year indirectly decreased physical health, mental health and chronic disease through increasing sleep disturbance and depressive symptoms.
Perceived stress indirectly reduced physical and mental health and increased chronic disease through decreasing vegetable and fruit consumption, and increasing sleep disturbance and depressive symptoms. These findings are consistent with contemporary literature and support the theory to a certain extent (Schwarzer &
Schulz, 2002). More specifically, previous research has indicated that stress is linked with an unhealthy diet (Mainous et al., 2010), sleep deprivation and with these
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health-compromising behaviours, participants may experience a reduced HRQOL
(Lau, 2013; Renzaho et al., 2013; Staniute, Brozaitiene, & Bunevicius, 2013; Takei et al., 2012; Heesch, van Uffelen, van Gellecum, & Brown, 2012; Kumarapeli,
Seneviratne, & Wijeyaratne, 2011; Renzaho et al., 2013) and increased risk of chronic disease (Renzaho et al., 2013; Segerstrom & O’Connor, 2012). In addition, previous research also indicated that stress was linked with depression
(Finnbogadottir, Dykes, & Wann-Hansson, 2014; Shapero et al., 2014; Tiwari et al.,
2014), which can in turn contribute to decreasing general health and well-being (Park et al., 2015; Renzaho et al., 2014; Seib et al., 2014) and an increase in the numbers of chronic conditions (Bajor et al., 2013). A cross-sectional study of 1257 females found that, after adjusting for marital status, education, income, employment status, pregnancy status, or being abused as a child, those who experienced abuse in their adult intimate relationships would be more likely to experience depression than others (Hegarty et al., 2004). In turn, depression significantly contributed to decreasing HRQOL (Pittman et al., 2012) and to the development of more health problems (Bajor et al., 2013).
Interestingly, while previous research showed that stress exposure could result in smoking (Krueger et al., 2011; Mainous et al., 2010) and excess alcohol drinking (Krueger et al., 2011; Lipsky et al., 2015; Slopen et al., 2011), as seen in
Figure 5.3, the variables of alcoholic drinks per day and cigarettes smoked per day were not retained in the final model. It is likely that because the number of women drinking alcohol and smoking among this population was low, the influences of stress on these behaviours could also not be detected in this study. This finding also reflected that even when exposed to stress, generally, Vietnamese older women had
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not taken to alcohol or smoking as a way to release their stress. This finding also suggested that stress might influence health differently in people from different cultures. Further investigations are warranted for more evidence about this issue.
Another interesting finding was that the influence of the number of SLEs on physical activities in this study was not congruent with the stress and health theory suggested by Schwarzer and Schulz (2002) and findings from other populations
(Stults-Kolehmainen & Sinha, 2014). Schwarzer & Schulz (2002) posited that those exposed to SLEs would be more likely to have a sedentary lifestyle (Krueger, Saint
Onge, & Chang, 2011; Mainous et al., 2010) and, as a result, people would experience decreased physical and mental health. However, among Vietnamese older women, those who reported more SLEs also reported more overall physical activity and these increased physical activity levels then increased their physical health. One possible explanation is that Vietnamese older women generally did not receive equivalent education and vocational training to men. The Vietnamese older women also had few opportunities for paid employment. In addition, during the last five decades, Vietnam has gone through wars and life after wars with limited resources
(Vietnamese Embassy Australia, 2013). These events may make women in Vietnam experience cumulative economic disadvantages and they may have believed that the source of most of their SLEs came from their low economic status. They may work harder rather than being sedentary to overcome this situation. Another possible explanation for this is that Vietnamese older women may have tried to increase their physical activity levels to avoid thinking too much about their SLEs. Again, this finding suggests that the influence of exposure to SLEs on health might be different
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among people from different cultures, and further investigations about stress and health from different cultures are warranted for more evidence about this issue.
Study 3 then showed the models describing the influence of SLEs on modifiable lifestyle factors, HRQOL and chronic disease among older women in
Vietnam and in Australia. Again Study 3 supported the stress and health theory to a certain extent (Schwarzer & Schulz, 2003). To be specific, both models showed that
SLEs indirectly influenced mental health through increasing depressive symptoms
(Schwarzer & Schulz, 2003), and the influence of SLEs in the previous year directly decreased mental health. However, as data in both the Vietnamese population and the
Australian population did not have physiological data, the influence of the number and impact of SLEs on physiological changes, HRQOL, and the number of chronic diseases among older women in both nations was not tested in the final model. Apart from this similarity, as the Vietnamese dataset was collected from a larger sample size, the model developed in the Vietnamese dataset was able to show more significant possible pathways among the variables. To be specific, among
Vietnamese women, the number of SLEs also indirectly influenced physical health, mental health and number of chronic diseases through increasing overall physical activity levels, and developing depressive symptoms. The impact of SLEs in the previous year also indirectly impacted on physical health, mental health and number of chronic diseases through increasing sleeping disturbance, and developing depressive symptoms.
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9.4 PERCEIVED STRESS, SOCIAL SUPPORT, AND THEIR ROLES ON THE RELATIONSHIP BETWEEN STRESSFUL LIFE EVENTS AND HEALTH 9.4.1 Perceived stress among older women in Vietnam and its mediation roles
As we could not ask the older women to endorse all the possible SLEs which happened to them or to their close relatives, Study 2 also used the Perceived Stress
Scale to measure perceived stress among the older women in Vietnam together with using the LSC-r. Study 2 found that Vietnamese older women who participated in the study reported low levels of perceived stress. These data provided a general picture about low stress perceptions among older women in Vietnam, but the range of scores provided additional information suggesting that there were a certain number of women who had a perceived stress score up to 34 out of a possible total of 40. So, there were women (n=43, 9.8%) who reported medium to high levels of stress.
Together with findings about SLEs, findings from this research highlighted a public health concern about modifiable lifestyle factors and health, especially mental health, among a certain number of older women in Vietnam and Australia.
Study 2, using SEM, was also able to examine the extent to which perceived stress mediated the influence of SLEs on the modifiable lifestyle factors, HRQOL and number of chronic diseases among older women in Vietnam. The study highlighted that perceived stress, rather than the number or the influence of SLEs, had a stronger influence on modifiable lifestyle factors, HRQOL and chronic disease among older women in Vietnam. This finding suggests that while asking the women to indicate their SLEs could help the healthcare professionals to understand the source of stress among their clients, measuring their stress perception would more sensitively estimate the influence of stress on their clients’ health. Therefore,
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healthcare professionals in Vietnam need to measure stress perception in addition to asking older women to endorse their experience of SLEs and their influence.
As seen in Chapter 6, perceived stress also mediated the influence of the number of SLEs on vegetable and fruit consumption, sleep disturbance, depressive symptoms, and mental health. These findings support the Stress and Coping theory
(Lazarus, 1966, 1984), which suggests that after SLEs exposure, different people may have different appraisals of and responses to SLEs, with perceived stress rather than the SLEs themselves having an impact on them. The mediation of perceived stress found in this study was also consistent with a previous study’s finding, which revealed that perceived stress could mediate the relationship between SLEs and depression. Taken together, the moderate influence (both direct and indirect) of perceived stress on health raises a concern about stress management among older women in Vietnam. The present health care system for older people in Vietnam mostly focuses on physical diseases, and available resources and facilities for mental health care are still limited. Stress can initiate or reinforce health-compromising behaviours such as smoking (Krueger, Saint Onge, & Chang, 2011; Mainous et al.,
2010), excess alcohol consumption (Krueger et al., 2011; Slopen, Williams,
Fitzmaurice, & Gilman, 2011), unhealthy diet, sedentary lifestyle (Krueger et al.,
2011; Mainous et al., 2010), sleep deprivation (Ware, Kosinski, & Keller, 1996), and elevated BMI (Barry & Petry, 2008). With these health-compromising behaviours, participants may experience worse HRQOL (Lau, 2013; Renzaho et al., 2013;
Staniute, Brozaitiene, & Bunevicius, 2013; Takei et al., 2012), and become more likely to have a chronic illness (Pyykkönen et al., 2010; Renzaho et al., 2013;
Segerstrom & O’Connor, 2012). In addition, previous research found that people
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exposed to stress would be more likely to develop depressive symptoms (Manuel,
Martinson, Bledsoe-Mansori, & Bellamy, 2012; Renzaho et al., 2013), and this could lead to a decreased HRQOL and more chronic conditions (Bajor et al., 2013). Thus, further service provision to manage stress and promote mental health, such as psychological counselling, and further social support services for Vietnamese older women are essential and should be applied.
9.4.2 Social support among older women in Vietnam and its buffering roles
As seen in Chapter 6, Vietnamese older women reported having two supporters on average. This finding is interesting because traditionally Vietnamese women live in an extended family, with their parents-in-law and siblings-in-law, partner, children, children-in-law, and grandchildren. However, first, the participants were aged 60-94, and the life expectancy in Vietnam is about 75 years (Vietnamese
Embassy Australia, 2013), so it was unlikely that their parents or parents-in-law still lived with them. Second, almost half (47.3%) of the participants were widowed, divorced or separated. Many of them did not have their partners by their sides.
Third, children, children-in-law, and even their grandchildren may have not stayed as close to them as expected because of their work or study. Fourth, as seen in the description of SLEs among older women in Vietnam, many of the older women reported that their family members were a source of stress. These Vietnamese older women might not have asked other family members for support, especially from those who were a source of their stress. Fifth, about 70% of the participants were not currently employed. They may have also been less likely to socialise with their colleagues as often as they had previously. Also, they may have believed that family-related SLEs should be kept inside the family. Therefore, they may have been
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hesitant to ask for support from friends who were external to the family. In addition, the women may have believed that all people had their own struggles and that they should manage their struggles themselves rather than asking for support. These reasons may explain why the reported total number of available supporters was low.
Yet, the social support scores were quite high, suggesting that these few supporters had a significant influence on these women’s lives.
Still, as seen in Chapter 6, about one tenth of older Vietnamese women reported having no supporters and around a third of women reported having no one to talk with about their problems, to keep their mind off things or to share their most private worries and fears with. About a quarter of older Vietnamese women had no one to understand their problems, to give them information, to help them understand the situation, or to give them good advice, and one in five did not have anyone to talk to when needed. There were also a small percentage of women who had no one to help when they were confined to bed. These findings suggest that many women still need further support. In the future, further support provisions such as psychological counselling, homecare, home visits and maybe aged care should be made available for these Vietnamese older women. These future interventions to provide services for stress management for older women in Vietnam should take notice of the role of their key support persons.
Regarding the correlates of social support, Study 2 found significant negative correlations between social support and the impact of SLEs in the previous year, perceived stress, the consumption of vegetables and fruits, depressive symptoms physical health, and mental health. These findings support the theory (Lazarus,
1966, 1984) which states that, psychologically, people will feel less stressed and are
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less likely to anticipate loss or harm when they deal with a situation in which their resources, such as instrumental support, emotional support, and successful coping experiences, meet the situational requirements. These findings are consistent with previous studies, suggesting that social support could alleviate the impact of SLEs on perceived stress (Gray-Stanley et al., 2010; Manuel et al., 2012; Salgado et al.,
2012). These findings are also consistent with previous studies (Manuel, Martinson,
Bledsoe-Mansori, & Bellamy, 2012; Salgado, Castaneda, Talavera, & Lindsay, 2012;
Staniute, Brozaitiene, & Bunevicius, 2013), which showed that social support had positive significant associations with HRQOL (Årestedt et al., 2013; Bekele et al.,
2013; Eom et al., 2013; Filazoglu & Griva, 2008; Hawkes et al., 2013; Manuel et al.,
2012; Park et al., 2015; Staniute et al., 2013; Yi et al., 2014; Zhou et al., 2010) and mental health (Ayers et al., 2009; Hou et al., 2015). Previous research has also shown the more social support people had, the less negative effects of SLEs on health they would experience (Manuel et al., 2012; Salgado et al., 2012), especially on mental health (Chen et al., 2009; Chojenta et al., 2012; Im et al., 2014; Wang et al., 2013).
Research also revealed that the influence of social support on health could be mediated by perceived stress (Zhou et al., 2010). Similar results were also found in the current study.
9.5 STRENGTHS AND LIMITATIONS OF THE STUDY
9.5.1 Strengths
The study had several strengths. First, the study was conducted in a previously unstudied population (Vietnamese older women). No reported study has been done to compare SLEs, modifiable lifestyle factors, depressive symptoms,
HRQOL, and chronic disease among older women in Vietnam and Australia.
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Findings from the study contributed to a comprehensive description about stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL and number and prevalence of chronic disease among older women in Vietnam for the first time in a comparison with Australian older women.
Findings from this study can provide useful information so that available interventions developed in Australia can be modified appropriately for use in
Vietnam to promote health among Vietnamese health older women.
Second, while there was a lack of Vietnamese research instruments to measure the relevant variables among older women in Vietnam, the current research has translated several valid English instruments into Vietnamese using standard translation and back-translation processes and examined their basic psychometric properties. This allows all the constructs to be measured using Vietnamese versions of the instruments, which achieved good translation equivalence, had acceptable internal consistency values and comparable test-retest reliabilities, and hence improving the reliability of the study’s findings.
Third, while cross-cultural comparison studies can be useful for consideration of future health interventions to people in different cultures, the comparisons which do not use the same measurements are likely to limit the validity of findings. This research used the same measurements and approach for data analysis for the
Vietnamese and Australian participants. This benefits data comparison internationally due to measurement equivalence (Buil, de Chernatony, & Martínez,
2012).
Fourth, the majority of previous studies have used binary analysis, simple regression analysis or multiple regression analysis for data analysis. This has limited
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investigation solely to focus on direct influences among variables and missed the opportunity to explore the indirect impact of SLEs. A combination of these direct and indirect influences among variables for a comprehensive model might increase statistical robustness. This research had a moderate sample size, with 440 from
Vietnam and 184 from Australia. The data in Vietnam were collected through face- to-face interviews rather than letting the participants fill in the self-report questionnaire by themselves, hence missing data were minimised. This allowed the sophisticated statistical data analysis to be used to explore the complex pathways by which SLEs may influence health among older women. The research also used SEM rather than binary correlation solely for data analysis, and statistical errors were also limited while both direct and indirect influences among study variables were fully explored.
9.5.2 Limitations
However, the current study also had some limitations that should be noted when interpreting the study findings. First, the cross-sectional design precludes examination of causality and the direction of the effects cannot be determined. Care should be taken when interpreting the nature of the relationships across the variables.
In this study, for example, the association between depressive symptoms and the number of chronic diseases needs to be interpreted with caution as participants could be more likely to have a chronic condition when they were depressed. It could also be that they were more likely to depressed when they had a chronic condition.
However, due to the constraints of time and resources, and given that a strong theoretical underpinning of the model specifications was used, a cross-sectional
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study carefully specified and using contextual theory is still a very useful approach, even though it does not provide the same strength of evidence as a cohort study.
Second, from a measurement perspective, as this study used self-report questionnaires for data collection, it might have introduced recalling, reporting and a social desirable bias. However, the participants were informed that the data were anonymous, that their responses were confidential and that no individual data would be presented. In addition, the researcher and the research assistants kept up a private conversation to ensure that no other people were around the participants during data collection. These actions could have limited the participants from over or under reporting. In future, objective measures such as physiological measurements could be used in conjunction with self-report to minimise recalling and reporting bias, and for a comprehensive measurement of other variables.
As the research instruments were originally developed in Western cultures, it would have been better if the Vietnamese versions of the instruments had been modified for Vietnamese culture prior to data collection on Vietnamese people. Also, other validity tests (such as criterion validity and concurrent validity), and other reliability tests (such as inter-rater reliability) were not conducted for the Vietnamese versions of the instruments. Due to constraints of time and resources, the researcher placed priority on the main scope of the research. It is recognised this is a limitation of the study as construct equivalence was not completely confirmed (Buil et al.,
2012). However, two of the instruments (CED-S for depression symptoms, SF-12) have been used previously in a Vietnamese population, and the rest of the study measurements have been previously used in various populations, including Asians,
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who have similar cultures to Vietnamese. It was assumed that these measurements may still have similar content validity for Vietnamese people.
Third, cross-cultural comparison studies usually expect some equivalences between two samples in terms of socio-economic characteristics and procedure for data collection (Buil et al., 2012). Yet, as presented in the results of Study 3, compared to the Australian sample, the Vietnamese women were older, more likely to have low income and education levels and to be widowed. Also, data were collected online in Australia and using interviewer-administered questionnaires in
Vietnam. These different methods could potentially confound the results. However, due to the variation of educational levels, vision problems, computer access and literacy among older women in Vietnam, online data collection was not feasible. The different socio-demographic characteristics of the two samples were addressed in the discussion chapter in relation to the interpretation of the studies’ findings.
Fourth, from the sample and sampling perspective, even though the
Vietnamese participants were chosen randomly from 16 rural and urban suburbs in
Vietnam, they were not chosen randomly from the Vietnamese population. Also, data from Australia were retrieved from a longitudinal study (2001-2012) which was conducted on a South-East Queensland population and had loss to follow up over the research period. This longitudinal Healthy Ageing of Women (HOW) study (CI
Anderson) commenced in 2001 and involved 1,500 randomly selected women from the electoral roll from six selected areas of South-East Queensland, but only 184 questionnaires were completed and returned in 2012. Therefore, the generalisation of the study findings is limited to the study populations rather than for the whole
Vietnamese and Australian population.
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Fifth, from the data perspective, data about social support and perceived stress were not available in the Australian dataset. Also, data about vegetable, fruit and tobacco consumption in the Australian dataset had not been collected as a continuous variable, as they were in the Vietnamese dataset. This limited the SEM data analysis using AMOS as continuous variables are required. Thus, the exploration of the influence of these variables could not be conducted on the
Australian dataset, and so the comparisons of more comprehensive models describing the influence of SLEs and perceived stress on modifiable lifestyle factors, depressive symptoms, HRQOL, and number of chronic diseases among older women in Vietnam and in Australia could not be performed. Also, data about fruit and vegetable consumption in Vietnamese women were only the estimated number of portions, which were calculated by the data collectors, based on what the participants told them about the approximated grams of vegetables and fruits consumed. This may have some variation from their actual consumption. In addition, as data in both the Vietnamese and Australian populations did not have physiological data, such as
DNA, serology, cortisol level, PCR (Seib, Whiteside, Humphreys, Lee, Thomas,
Chopin, Crisp, O’Keeffe, et al., 2014), the influence of SLEs and perceived stress on health through physiological changes among older women in both nations was not tested in the final model.
Sixth, the socio-demographic characteristics might have influenced the final model of the SLE influences on modifiable lifestyle factors, depressive symptoms,
HRQOL and chronic disease among older women in two nations. However, they were not included in the modelling because SEM requires a large sample size. To be specific, in order to use SEM, sample size is expected to be equal or larger than ten
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times of the number of parameters in the model (parameters = variables + arrows
(paths) in the model). Including all potential socio-demographic variables into the model would make the model more complex and require a larger sample size, which was not feasible for the scope of this research. Furthermore, modelling using SEM and AMOS requires continuous variables in the model. Data about income, marital status, education levels, and employment status were categorical data. Therefore, including these variables in the modelling was not possible. In addition, the aims of this research were to provide better understanding about SLEs and their influences on health so that interventions to modify lifestyle, manage stress and promote health for older women could be implemented in the future. Therefore, including non- modifiable variables in the modelling appeared to provide fewer implications for future interventions.
Finally, since the final model describing the influence of the number and impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and number of chronic diseases among older women in Vietnam and in Australia was the result of model modification, the model fit requires further studies in other populations and settings to support the model’s consistency.
9.6 RECOMMENDATIONS FOR FUTURE RESEARCH AND IMPLICATIONS FOR HEALTHCARE PRACTICE AND POLICY This research was an initial effort to understand stressful life events, perceived stress, social support, modifiable lifestyle factors, depressive symptoms,
HRQOL and chronic disease among older women in Vietnam. The research also investigated the influence of stressful life events, perceived stress and social support on modifiable life style factors, depressive symptoms, HRQOL and number of chronic diseases among older women in Vietnam. The research took a further step by
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comparing the Vietnamese data to an available Australian dataset to understand differences in the stressful life events, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in these two countries.
Despite the limitations, this research provides, for the first time, knowledge about stressful life events, perceived stress, modifiable lifestyle factors, depressive symptoms, HRQOL and chronic disease among older women in Vietnam. The research also comprehensively tested direct and indirect influences of the number and impact of stressful life events, perceived stress on modifiable life style factors, depressive symptoms, HRQOL and number of chronic diseases among older women.
Finally, the research provided useful comparative data about stressful life events, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in Vietnam and in Australia. Findings from this research are useful in increasing understanding about stressful life events, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic diseases among older women in
Vietnam and in Australia. The findings also highlight the importance of stress management for better health and well-being among older women.
As the ageing populations in Vietnam and Australia have increased significantly and women are more vulnerable to stress, several implications can be taken from this research to apply to future research and healthcare practice about older women’s health. The implications gained from these research findings will also be useful for other Asian and Western countries that have similar characteristics to the research populations.
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9.6.1 Recommendations for future research
First, a focus group interview to assure the cultural adaptation for the
Vietnamese versions of the research instruments should be conducted to evaluate the content validity of the Vietnamese versions of the research instruments.
Modification of the instrument might be required as a result of focus group interviews for cultural appropriateness. The modification can be done by conducting a comprehensive focus group interview among experts in translation process and the
Vietnamese participants to explore their thoughts about the measurement. The experts could provide a comprehensive content validity assessment of Vietnamese versions of the instruments (Polit & Beck, 2006; Polit, Beck, & Owen, 2007). This step will increase the possibility that the study can capture the construct better for the target population. It is also recommended to assess and endorse further validity and reliability of the Vietnamese versions of the instruments. To be specific, future exploratory factor analysis, confirmatory factor analysis, and concurrent reliabilities
(Polit & Beck, 2006; Polit et al., 2007) of the Vietnamese versions of these research instruments should be conducted. As a result of these validations, the Vietnamese versions of the instruments used in this study will have improved validity and reliability for future data collection in later studies.
Second, as many Vietnamese older women reported no exercise, high prevalence of sleep disturbance, and high prevalence of major depression, further investigation of the correlates of these lifestyle factors may provide more information so that lifestyle modification and mental health promotion can be implemented.
Therefore, it is recommended to further explore the correlates of exercise, sleep disturbance and depression among older women. Quantitative research methods such
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as a cross-sectional survey and longitudinal study could explore the factors influencing their exercise, sleep disturbance, and depression. Qualitative research methods, such as focus-group interviews, would provide in-depth understanding of reasons why older women in Vietnam are less likely to exercise. Next, a randomised control trial may be then conducted to test modifications to lifestyle and to promote health, especially mental health, among older women in Vietnam.
Third, future studies should include physiological data such as DNA, serology, cortisol level, and PCR (Seib, Whiteside, Humphreys, Lee, Thomas,
Chopin, Crisp, O’Keeffe, et al., 2014) to test the full model describing the influence of SLEs and perceived stress on modifiable lifestyle factors, depressive symptoms,
HRQOL, and number of chronic diseases among older women. Ideally in the future, experimental designs or longitudinal designs with large sample sizes are needed to determine the causal relationships among the variables; and more objective measures could be used in conjunction with self-report to minimise recalling and reporting bias and for a comprehensive measurement of other variables. Also, the socio- demographic characteristics might have influenced the final model of the SLE influences on modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease among older women in two nations. Including all of potential socio- demographic variables into the model would allow the model to describe the roles of these factors in the model. It is also suggested that rather than using SLEs to predict chronic disease, future studies could investigate how psychosocial stress changes individual chronic conditions, such as hypertension or coronary heart disease. M-plus software can perform SEM with categorical variables while AMOS limits its data analysis on modelling with continuous variables. While data collected are not
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always in continuous scales, using M-plus would maximize the comprehensive modelling of the study variables. Therefore, for a comprehensive modelling in the future, it would be more appropriate to use M-plus software for data analysis rather than AMOS.
Finally, since the final model describing the influence of the number and impact of SLEs on modifiable lifestyle factors, depressive symptoms, HRQOL and number of chronic diseases among older women in Vietnam and in Australia was the result of model modification, a validation of the model in a similar population in the future is necessary. The models reported were developed in a specific population, so in order to apply these models to other populations it is important to have cross- validation of the model. For the generalisation of the study findings, random sampling should be applied for the whole population.
9.6.2 Implications for healthcare practice and policy
Currently, Australia has several available programs to promote HRQOL and to manage chronic disease for older women. Australia also has a dietician training system (from bachelor degree to doctoral degree), which has provided a number of qualified dieticians to work as clinical personnel or counsellors in different healthcare settings, including hospitals, and primary healthcare services in community. Their services can be paid by their Medicare (Australian governmental medical health insurance) or private medical health insurance. Therefore, Australians can access expert knowledge about diet when needed. In addition, information about healthy diet is also available and accessible for Australians in several official websites, booklets, and text-books. Moreover, Australia frequently runs campaigns to promote healthy diet in the community. Last but not least, Australia has strict laws
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and systems controlling Food Safety from ingredients to process, preservation and trading in the market. This contributes to limited food contamination and to promote consumption of healthy food among Australians.
Similarly, Australia has detailed laws about alcohol and tobacco consumption in terms of permitted time, place and amount. Advertisements of tobacco are prohibited in Australia. High taxes have been applied on tobacco and alcohol.
Surveillance, security and police are in place to ensure the laws of alcohol drinking and tobacco smoking are applied strictly, especially in public areas. Physical education has been implemented at early stages of life in Australia. In addition, walking and cycling are promoted in various ways, including campaigns in schools and workplaces. A number of qualified of physical activity/ exercise personnel exist in Australia. Information about physical activity and exercise is available and accessible. Australians can access exercise counsellors with their Medicare. More importantly, besides sport centres, a number of complex community facilities have been built to promote physical activities, such as secured parks having well- maintained playgrounds, restrooms and exercise lounges inside workplaces.
Therefore, Australians can have exercise at times convenient to them.
Mental health care has been implemented in Australia in various ways.
Australia has professional psychosocial counsellors in schools, in workplaces and working in independent organisations, such as Lifeline. These services are confidential. Access to many of these health services are free of cost, covered by
Medicare or health insurance.
To promote health-related quality of life and manage chronic disease among
Vietnamese people, firstly, mass media should be used to deliver information about
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recommended portions of healthy eating, recommmed levels of physical activities and exercise, and sleep problems. As the majority of Vietnamese older women did not receive high education and have very limited access to the internet or computers, concise booklets rather than detailed textbook or websites about recommended type and amount food can bring more benefits for Vietnamese older women. Also, rather than focusing on limitation of high energy food and weight management as it is in
Australia, information booklets about diet for Vietnamese older women may focus more on controlling salt and nutritional food intake. This can be more beneficial for those living in rural areas (70% of Vietnamese older women).
Together with raising awareness in the community, good training programs for nutritional/ exercise/ mental health care personnel are required in Vietnam.
Qualified staff need to be available to assess community health problems. With regards to stress, findings from this study suggest that in the future, assessment of stress should be considered for Vietnamese older women. In this assessment, family- related SLEs and war-related SLEs (as listed in Chapter 5) should be included. In addition, rather than assess for experience of SLEs solely, the assessment should include assessment of stress perception. Also, since many of the older women in
Vietnam reported sleep disturbance and signs and symptoms of mild and severe depression, further clinical assessment for sleep problems and depression are recommended. During these assessments, it would be useful to seek understanding about how older women in Vietnam cope with their stress. This additional information would provide background so that modifiable lifestyle factors can be more easily modified and their sleep problems and depression could be managed better in the future.
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Qualified staff in lifestyle and mental health can also provide expert consultations about diet/exercise and mental healthcare for community people. One of example is that as chronic disease may inhibit older women from performing these healthy behaviours appropriately for their own circumstances, expert advice should be provided for those with special requirements. To assist Vietnamese older women, who have more chronic conditions and higher prevalence of arthritis, hypertension, and heart disease, to adopt appropriate healthy behaviours and who may not be able to do strenuous exercise, to have adequate exercise, tai chi instead of strenuous exercise might be considered as an alternative. Yet, currently, the small number of staff working mostly in central hospitals limits the access of community people for experts advice about diet, exercise and psychosocial counselling.
The Vietnamese government should have more involvement in controlling food safety. Strict laws and management systems need to be in place to control food safety, especially vegetable and fruits contaminations, which are currently at alarming rates. Also, as dental problems are common among Vietnamese older women. For promoting healthy food consumption, dental care for older people may also assist Vietnamese older women in increasing higher levels of a healthy diet.
Similarly, as Vietnamese older women usually believe in collectivism, different from those in Australia who mostly believe in individualism, community exercise programs, which encourage older people to practice exercise, such as Tai-chi in a big group, rather than individual training can be more promising for Vietnamese women.
Thirdly, while many Vietnamese older women have low income, social welfare systems need to provide better financial support for this population. With financial security, Vietnamese older people may not have to work at extremely
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physical levels and can live independently if needed to avoid any abuse related to financial dependences. To care for those with stress, sleep problems and depression, primary mental health care in Vietnam needs to be strengthened and more professional. Confidential psychological counselling can be helpful for Vietnamese older women, especially those suffering from domestic abuse.
Fourthly, currently, the number of social supporters was low among older women in Vietnam. Also, as chronic disease was common among older women in
Vietnam and it has been increasing, there is an increasing need to enhance healthcare services for chronic disease management for this population. Further chronic disease management support services, such as home visits, homecare, and culturally appropriate aged care, should be implemented and enhanced in the future. To prepare for these service developments, training is required for healthcare staff. Healthcare facilities need more investment and strict healthcare laws are also needed to protect both healthcare professionals and clients.
As discussed, generally the income of older women in Vietnam was low.
About 13.9% in rural areas and 46% in urban areas have healthcare insurance
(Vietnamese Ministry of Health, 2006). Among older people, only 24.5% had health insurance (Vietnamese Ministry of Health, 2006). At the moment, health insurance in
Vietnam basically covers for clinical physical healthcare in hospitals (Vietnamese
Ministry of Health, 2006). To maximise the utilisation of primary chronic disease management support services and mental healthcare services among older women in
Vietnam, older people need to have health insurance, while the healthcare insurance system needs to consider inclusion of relevant extra cover.
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9.7 CONCLUSION
The literature revealed that ageing is associated with decreased HRQOL and increased risk of chronic disease. Compared to men, women appear to be more vulnerable to stress, and are more likely to have reduced HRQOL and several chronic diseases. Limited numbers of studies have investigated the influences of exposure to SLEs on HRQOL and number of chronic diseases from gender perspectives.
Theories about stress and health suggest that exposure to SLEs may lead to a decrease in general health and increase of chronic disease by changing lifestyles and developing depressive symptoms. Stress theory also suggests that with exposure to similar SLEs, different people may have different responses as they appraise the stressors differently based on their resources and coping. Yet, to date, these patterns in different cultures have been only been investigated within a limited context.
In Vietnam, gender roles are quite clear and women in this context have unique expectations placed on them. During the last century, many dramatic socio- economic and historical changes have occurred in Vietnam. Accompanying these changes, domestic violence and warnings about food safety have also increased.
Within this context, Vietnamese older women might experience different SLEs, lifestyles and health outcomes. Research about SLEs and health has been conducted in Australia. Yet, knowledge about SLEs, lifestyle, depressive symptoms, HRQOL, and chronic diseases in Vietnam is still limited.
This research described SLEs, perceived stress, social support, modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease and tested the
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goodness of fit between the model describing the pathways connecting SLE, perceived stress and modifiable lifestyle factors, depressive symptoms, HRQOL, and chronic disease using data from older women in Vietnam. The study also explored the roles of social support and perceived stress in the relationship between SLEs and health. Finally, the study compared findings from a Vietnamese dataset with those from an Australian dataset.
The research found that Vietnamese older women experienced a similar number of SLEs, prevalence of stroke, T2DM, arthritis, and osteoporosis to those in
Australia. Different from Australians, family-related and war-related stress concerned Vietnamese older women. The number of chronic diseases was also higher than in Vietnamese women, and their physical health levels were low. This indicates that more healthcare services to manage chronic disease and promote physical health among older women in Vietnam are required.
The research also found that many older women in Vietnam did not have a healthy diet, nor did they exercise, and they experienced sleep disturbance and reported several depressive symptoms. While the current healthcare system in
Vietnam has less focus on health promotion and mental healthcare, these findings highlighted that interventions to modify these lifestyle factors and promote mental health in this population need to be developed in the future.
Regarding the impact of SLEs, the research found that exposure to SLEs increased depressive symptoms and decreased mental health for both populations, even though the patterns by which SLEs influence modifiable lifestyle factors and health were different for older women in Vietnam and Australia. Exploration of perceived stress and social support roles showed that rather than SLEs themselves
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influencing health, perceived stress had a stronger influence and the impact of SLEs on health can be buffered with higher levels of social support.
Despite the limitations, findings from this research provide useful information for future research, healthcare practice and policy. With this information, available Australian interventions can be modified to promote health for Vietnamese older women in the future in the hope that older women in Vietnam will experience an improved and healthier ageing. The implications gained from this research can also be useful for other Asian and Western countries which have similar characteristics to the study research populations.
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Appendix A: Ethical approval in Vietnam
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Appendix B: Ethical approval in Australia
Dear Dr Charrlotte Seib and Mrs Tiet Hanh Dao Tran Project Title: The impact of psychosocial stress and modifiable lifestyle factors on health-related quality of life and chronic disease among older women in Australia and Vietnam: A cross-cultural comparison Ethics Category: Human - Low Risk Approval Number: 1400000256 Approved Until: 2/06/2018 (subject to receipt of satisfactory progress reports) We are pleased to advise that your application has been reviewed and confirmed as meeting the requirements of the National Statement on Ethical Conduct in Human Research.
I can therefore confirm that your application is APPROVED. If you require a formal approval certificate, please advise via reply email.
CONDITIONS OF APPROVAL Please ensure you and all other team members read through and understand all UHREC conditions of approval prior to commencing any data collection: > Standard: Please see attached or go to www.research.qut.edu.au/ethics/humans/stdconditions.jsp > Specific: None apply
Decisions related to low risk ethical review are subject to ratification at the next available UHREC meeting. You will only be contacted again in relation to this matter if UHREC raises any additional questions or concerns.
Whilst the data collection of your project has received QUT ethical clearance, the decision to commence and authority to commence may be dependent on factors beyond the remit of the QUT ethics review process. For example, your research may need ethics clearance from other organisations or permissions from other organisations to access staff. Therefore, the proposed data collection should not commence until you have satisfied these requirements.
Please don't hesitate to contact us if you have any queries.
We wish you all the best with your research. Kind regards Janette Lamb on behalf of the Chair UHREC Research Ethics Unit | Office of Research | Level 4 88 Musk Avenue, Kelvin Grove | Queensland University of Technology p: +61 7 3138 5123 | e: [email protected] | w: www.research.qut.edu.au/ethics/
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Appendix C: Permission letter to derive HOW4 data (2012) for secondary data analysis
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Appendix D: QUT Postgraduate Award
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Appendix E: QUT Grant in Aid Award
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Appendix F: Graduate Scholar Award
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Appendix G: Write up scholarship award
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Appendix H: Certificate of completion “Teaching Advantage Program”
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Appendix I: Certificate of completion “Leadership and Communication Module”
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Appendix J: Certificate of completion “Project Management Module”
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Appendix K: Questionnaire (English version to collect data in Vietnam)
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Appendix L: Results of the test of normality
Results of the test of normality in the Vietnamese dataset (n=440)
Kolmogorov Smirnova Shapiro-Wilk Statistic Sig. Statistic Sig. Number of SLEs .150 .000 .900 .000 Impact of SLEs in the previous year .217 .000 .771 .000 Perceived stress .166 .000 .882 .000 Numbers of supporters .199 .000 .655 .000 Social support .111 .000 .916 .000 Average number of vegetable serves .183 .000 .909 .000 consumpted per day Average number of fruit serves .198 .000 .861 .000 consumpted per day Amount of alcohol consumed in the .525 .000 .061 .000 previous week Average number of cigarettes smoked in .520 .000 .041 .000 the previous week Average number of days practiced exercise .402 .000 .620 .000 Overall physical activity levels .150 .000 .960 .000 Sleeping disturbance .084 .000 .960 .000 BMI .062 .000 .907 .000 Depressive symptoms .171 .000 .848 .000 Physical health .109 .000 .951 .000 Mental health .199 .000 .854 .000 Numbers chronic diseases .156 .000 .922 .000
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Results of the test of normality in the Australian dataset (n=184)
Kolmogorov- Shapiro-Wilk Smirnova
Statistic Sig. Statistic Sig.
Number of SLEs .154 .000 .895 .000
Impact of SLEs in the previous year .232 .000 .681 .000
Number of alcohol drinks per session .241 .000 .634 .000
Number of caffeine drinks per day .106 .000 .949 .000
Overall physical activity levels .128 .000 .967 .000
Sleeping disturbance .090 .000 .948 .000
BMI .085 .000 .972 .000
Depressive symptoms .156 .000 .946 .000
Physical health .178 .000 .830 .000
Mental health .248 .000 .851 .000
Numbers chronic diseases .158 .000 .890 .000
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Appendix M: Accepted abstracts for oral conference presentations
Oral conference presentation 1 The Aging & Society: The Fifth Interdisciplinary Conference, Washington D.C, USA from November 5 to 6, 2015
Stressful life events and health among elderly women in Vietnam
Dao Tran, T.-H., Seib, C. & Anderson, D. (5-6/11/2015)
Abstract
Background: Exposure to stressful life events has been linked with poor lifestyle behaviours and decrements in health status. Despite improvements in our understanding of the possible impacts of stress on health, knowledge about sequelae of stressful life events in some population groups, particularly among older women from Southeast Asia, is still limited. This study examines the prevalence and correlates of stressful life events in women aged 60 years and older from Vietnam.
Methods: A total of 440 women aged 60 years and older in Vietnam participated in this cross-sectional study. A questionnaire was used to collect data on stressful life events, vegetable and fruit consumption, physical activity, sleeping disturbance, depression, mental and physical health from older women in Vietnam. Descriptive analysis was used to describe the prevalence of stressful life events, and structural equation modelling statistical analysis was used to model the impact of stressful life events on health among women aged 60 years and older in Vietnam.
Findings: This study found that older women in Vietnam experienced a variety of stressful life events including loss of a loved person, miscarriage, serious money
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problems, and caring for someone with serious health issue etc. Event exposure not only influenced mental health directly (β = -0.12, p <0.05) but also seemed to indirectly influence both mental and physical health through increasing physical activity level (β = 0.13, p <0.05) and depression level (β = 0.25, p <0.05).
Conclusions: This study suggested that stress is likely to impact women’s health through a variety of pathways and further research and service provision is necessary to promote Vietnamese women’s health.
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Oral conference presentation 2: to be presented The 21st International Council on Women’s Health Issues (ICOWHI) Congress, in Baltimore, Maryland, USA, from November 6 to 9, 2016.
Sleeping disturbance among older women in Vietnam: Results from the Vietnamese Women’s Wellness Research Program
Tiet-Hanh DAO-TRAN1, Debra ANDERSON2, Charrlotte SEIB3.
Abstract
Background: Sleep disturbance can negatively influence women’s health and well- being and is likely to increase with age. While the number of women aged 60 and over are increasing in Vietnam the prevelence and correlates of sleep disturbance among older women is still unclear.
Objectives: This study aims to explore the prevalence and correlates of sleep disturbance among older women in Vietnam.
Research methods: A cross-sectional survey collected data from 440 older women from 17 rural and urban suburbs in Vietnam. Structured questionnaires were used to gather data about age, marital status, employment status, estimated total average income, educational attainment, body mass, physical activity, perceived stress, self- reported health status, chronic disease, and sleep disturbance. Descriptive analysis was used to describe the prevalence of sleeping disturbance. ANOVA, t-test, Pearson correlation were used to investigate the correlates of sleeping disturbance.
Summary of findings: The average GSDS score was 36.28 (SD = 22.68) and 38.9 % of women met the criteria for significant sleep disturbance (i.e., GSDS ≥43). Many older Vietnamese women reported difficulty maintaining sleep (71.8%), sleep latency (43.2%), reduced sleep quality (43.4%), and early waking (37.5%). About one fourth of older women also reported daytime sleepiness (24.8%, N=109).
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Bivariate analysis suggested that women who were unemployed reported more sleep disturbance than who were currently employed (t (438) =2.04, p<0.05); those who had income per month of less than 80 USD reported more sleep disturbance than those who reported income per month of 80 USD and above (t (438) =2.95, p<0.01); and those who were widowed reported more sleep disturbance than those who lived with their partners (F (4) = 2.63, p<0.05). Positive correlations were noted between perceived stress (r = 0.22, p <0.01), number of chronic conditions (r= 0.26, p <0.01), and sleep disturbance while negative correlations were observed for physical health
(r = -0.42, p <0.01), mental health (r = -0.32, p <0.01), physical activity (r = -0.13, p
<0.01), and exercise (r = -0.13, p <0.01).
Conclusion: Findings suggested that sleep disturbance was relatively common among older women in Vietnam, especially among those who reported greater social disadvantage. Strategies that target stress and chronic disease management and increase physical activity are likely to reduce sleep disturbance in this population.
Key words: Correlates; Older women; Prevalence; Sleeping disturbance; Vietnam.
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