HSE Health & Safety Executive

Lay conceptualisations of occupational disease

Prepared by Risk Analysis, Social Processes & Health (RASPH) Group for the Health and Safety Executive 2006

RESEARCH REPORT 469 HSE Health & Safety Executive

Lay conceptualisations of occupational disease

Professor Eamonn Ferguson Dr Claire Lawrence Dr Pete Bibby Ms Joanna Leaviss Dr Nima Moghaddam Risk Analysis, Social Processes & Health (RASPH) Group School of Psychology University of Nottingham Nottingham NG7 2RD

ObjectivesPeople’s beliefs about the causes, treatments, symptoms, and duration etc. of an illness form a model that influences what they define as illness and how they respond to it (treatment seeking, absenteeism). Members of the lay public and the experts they might consult about their illnesses may have very different models of illness. Further, lay and expert groups may perceive different sources of information as more or less trustworthy. Any differences are important to examine, as such differences may results in poor communication and treatment compliance. These ideas have never been tested with respect to a comparison of occupational and non­occupational illness. This was the aim of this project.

MethodsDifferences between lay and expert models of illnesses were examined using (1) an interview study with expert (occupational physicians, occupational psychologists: N =21) and lay participants (N = 19), (2) a field based experiment based on random sample of the UK population (N = 1947) compared to a sample of experts (N = 240) and (3) a structural cognitive mapping study with experts (N = 15) and lay participants (N = 15). Four illnesses were studied: multiple sclerosis and lung cancer were selected as they were generally viewed as non­ occupational diseases, with asthma as potentially occupational and stress as occupational.

ResultsExperts were more likely to see work conditions as a cause of stress than lay people and viewed external impersonal sources (HSE, employers) as offering more trustworthy information about the diseases. Lay participants viewed inter­personal sources of information (friends, GPs) as more trustworthy. Lay participants were more likely to endorse work related consequences for illnesses than experts. Experts were more knowledgeable about medically well known illnesses (lung cancer and asthma), and in general were more confident.

ConclusionsExperts are more likely to perceive work characteristics as causes of stress. This may lead experts – who advise lay people – to over­emphasise work characteristics as a cause of stress.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.

HSE BOOKS © Crown copyright 2006

First published 2006

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ii Acknowledgements

We would like to acknowledge the help and advice from Dr Rosanna Cousins and Professor Colin MacKay with respect to the work reported. We are extremely grateful to all participants (lay and expert) who gave up their time to take part in the work. We hope that the results and findings justify their efforts.

iii iv CONTENTS

CONTENTS V

EXECUTIVE SUMMARY IX

1 GENERAL OVERVIEW & INTRODUCTION 1

1.1 BACKGROUND 1

1.2 CONCLUSIONS AND STUDY QUESTIONS 10

1.3 OBJECTIVES OF THE PROJECT 10

1.4 MAIN DELIVERABLES OF THE PROJECT 11

1.5 THE STRUCTURE OF THE REPORT 11

2 METHODS, SAMPLES AND MATERIALS 12

2.1 PILOT STUDY 1: PILOT OF DISEASE TYPES 12

2.2 MAIN STUDY 1: LAY AND EXPERT INTERVIEWS 14

2.3 PILOT STUDY 2: PILOTING & DEVELOPING THE QUESTIONNAIRE MATERIALS TO BE USED IN THE RANDOMISED FIELD STUDY 15

2.4 MAIN STUDY 2: NATIONAL RANDOMISED FIELD-BASED EXPERIMENT AND TARGETING OF EXPERTS 26

2.5 MAIN STUDY 3: EXPLORATION OF LAY AND EXPERT ‘COGNITIVE MAPS’ 30

3 CLASSIFYING ILLNESSES AS OCCUPATIONAL OR NON-OCCUPATIONAL 32

3.1 RESULTS FROM PILOT STUDY 1: IDENTIFYING OCCUPATIONAL AND NON-OCCUPATIONAL DISEASES 32

3.2 RESULTS FROM MAIN STUDY 1: LAY AND EXPERT INTERVIEWS 33

4 PERCEPTIONS OF ILLNESS CAUSATION 38

4.1 COMPARING LAY AND EXPERT PERCEIVED CAUSES OF ILLNESS (ACROSS ALL 4 ILLNESSES) 38

4.2 COMPARING LAY AND EXPERT PERCEIVED CAUSES OF ILLNESS (BY ILLNESS) 39

4.3 INTERIM CONCLUSIONS 43

4.4 LAY AND EXPERT MODELS OF ILLNESS CAUSATION 43

4.5 INTERIM CONCLUSIONS 46

4.6 GENERAL DISCUSSION AND IMPLICATIONS FOR EDUCATION AND TRAINING 46

v 5 TRUST IN SOURCES OF INFORMATION 48

5.1 PERCEIVED TRUSTWORTHINESS OF INFORMATION SOURCES (ACROSS ILLNESSES AND EXPERTISE) 48

5.2 COMPARING LAY AND EXPERT PERCEIVED TRUSTWORTHINESS OF INFORMATION SOURCES (ACROSS ILLNESSES) 49

5.3 INTERIM CONCLUSIONS 49

5.4 COMPARING LAY AND EXPERT PERCEIVED TRUSTWORTHINESS OF INFORMATION SOURCES (BY ILLNESS) 49

5.5 INTERIM CONCLUSIONS 53

5.6 REGRESSING ILLNESS REPRESENTATIONS ONTO SOURCES 53

5.7 DISCUSSION 61

6 THE ROLE OF RAW AND CALIBRATED KNOWLEDGE 62

6.1 COMPARING LAY AND EXPERT KNOWLEDGE, CONFIDENCE, AND CALIBRATION 62

6.2 INTERIM CONCLUSIONS 65

6.3 ASSOCIATIONS BETWEEN ILLNESS REPRESENTATIONS AND KNOWLEDGE CALIBRATION 65

6.4 INTERIM CONCLUSIONS 66

6.5 GENERAL DISCUSSION 66

7 ILLNESS REPRESENTATIONS FOR THE FOUR DISEASES 67

7.1 COMPARING LAY AND EXPERT ILLNESS REPRESENTATIONS (BY ILLNESS) 67

7.2 INTERIM CONCLUSIONS 70

7.3 COMPARING LAY AND EXPERT PERCEPTIONS OF SYMPTOM SEVERITY/ILLNESS IDENTITY (BY ILLNESS) 70

8 EVALUATION OF THE DEVELOPED COGNITIVE MAPS 74

8.1 EXPERT FEEDBACK 74

8.2 LAY FEEDBACK 74

9 FINAL CONCLUSIONS AND RECOMMENDATIONS 76

9.1 CONCLUSIONS 76

9.2 RECOMMENDATIONS – PRACTICAL IMPLICATIONS 77

REFERENCES 79

vi APPENDICES 82

APPENDIX 1 METHODS FOR DEVELOPING LAY MODELS 83

APPENDIX 2 METHODS FOR DEVELOPING EDUCATIONAL MATERIALS 85

APPENDIX 3 METHODS FOR DEVELOPING KNOWLEDGE QUESTIONS 87

APPENDIX 4 MATERIALS USED IN ALL STUDIES 88

PILOT STUDY 89

INTERVIEW STUDY 91

NATIONAL SURVEY STUDY 105

COGNITIVE MAPPING STUDY 126

APPENDIX 5 CALCULATING ILLNESS REPRESENTATION SCORES FROM QUESTIONNAIRE MATERIALS 134

vii viii EXECUTIVE SUMMARY

BACKGROUND

Members of the public hold lay or cultural models about illness/disease and this is known to be related to a variety of illness related behaviours (e.g., medication adherence, GP visits). However, this approach has not been applied to occupational illness: it is not known to what extent people see work as a cause of particular illnesses and how these illnesses are viewed. For example, are they seen as long lasting and chronic or short lived and cyclical? Finally, lay members of the public are likely to seek advice on illness from experts – who will also have a representation of various illnesses. How do lay and expert representations differ, and what implication does this have for potential miscommunication between the lay and expert groups?

METHODS

To address these questions a series of interview studies with experts and lay people were conducted. This was followed by a national field based experiment based on a random sample of the UK population examining lay perceptions of multiple sclerosis, lung cancer, asthma and stress (N = 1947). Multiple sclerosis, lung cancer were selected as they were generally viewed as non-occupational, with asthma as potentially occupational and stress as occupational. This sample was compared to a sample of experts (N = 240) in occupational illness, stress research, occupational and health psychology. A final study using structural cognitive mapping procedures – to produce visual representations – was used to further explore lay and expert samples representation of the 4 illnesses.

MAIN FINDINGS

There are a number of key findings and these are highlighted below:

1. Experts are more likely to see work conditions as a cause of stress than lay people. 2. Lay people are less likely to see demographic factors (age, sex) as a cause of illness. 3. Lay participants view inter-personal sources of information (friends, GPs) as more trustworthy and experts view external impersonal sources (HSE, employers) as offering more trustworthy information about the diseases. 4. Trust in the HSE and occupational physicians was related to work-related practical advice about work relationships (e.g., people with the disease should not do certain jobs). 5. Trust in GPs and family and friends were associated with more inter-personal actions – for example stopping working, informing their employer. 6. Trust in the mass media was only related to perceptions of stress. 7. Experts were more knowledgeable about medically well known illnesses (lung cancer and asthma), and in general were more confident. 8. Both groups were under-confident with respect to their knowledge about stress. 9. For MS, lung cancer and asthma, experts were more likely than lay participants to endorse illness representations of coherence and control, whereas lay participants were more likely to endorse effects on work.

ix GENERAL CONCLUSIONS

Lay and expert differences exist. The main issue appears to be that experts, compared to lay participants, are more likely to perceive work characteristics as causes of stress (disease is potentially more work related and less well defined). This may lead experts – who advise lay people – to over emphasise work characteristics as a cause of stress. Also both lay and expert groups perceive illness as multi-causal and this is especially the case for illnesses that are less well medically defined. Also lay participants see inter-personal (less scientific) sources of information as more trust worthy. As such, experts should take this into consideration when communicating risk.

x 1 GENERAL OVERVIEW & INTRODUCTION

1.1 BACKGROUND

1.1.1 What is occupational illness and how many are affected? Occupational illness has been defined (for the purposes of assessment) as any illness, disability or other physical/mental problem caused or made worse by current or past work (Jones et al., 2005). Available data on occupational illness is derived from four main statistical sources (HSC/E, 2005): (1) Self- reported Work-related Illness (SWI) based on the Labour Force Survey, (2) surveillance data from specialist doctors in The Health and Occupation Reporting network (THOR), (3) claims for disablement benefit under the Department for Work and Pensions' Industrial Injuries Scheme (IIS), and (4) numbers of deaths from mesothelioma and other occupational diseases.

The latest self-report data (SWI; 2004/05) indicates that around 2 million people in the UK suffer from ill health that they perceive to be work-related. Just over half of these cases are musculoskeletal disorders (central estimate: 1,102,000). Around a quarter of cases are accounted for by stress, depression, or anxiety (estimate: 509,000). The third most prevalent work-related illness in self-report data is respiratory disease (estimate: 137,000 cases). Self-reported work-related illness is most prevalent in industry areas of health/social work (estimated 4,800 cases per 100,000 people), public administration (4,300 per 100,000), and construction (3, 900 per 100,000). In 2004/05, 28.4 million working days were lost due to work-related ill health: equivalent to over 1 day lost per worker.

Occupational physicians and disease-specialist doctors saw around 23,000 new cases of occupational illness each year between 2002 and 2004 (according to available THOR data). The two most prevalent illness types were mental ill health (estimate: 7500 cases per year) and musculoskeletal disorders (estimate: 7100 cases), as in self-report data. An average of over 7500 cases per year are assessed for disablement benefit under the IIS (based on data from 2002-04). Most commonly, cases relate to vibration white finger, carpal tunnel syndrome and respiratory diseases associated with a history of exposure to substances such as asbestos.

Death certificates indicate that several thousand people die each year from diseases caused by past work exposures. In 2003, there were nearly 1900 deaths from mesothelioma (a cancer related to asbestos exposure).

1.1.2 Why the lay perspective is important The figures reported above for occupational illness indicate that this is a major concern in terms of employee health and safety as well as the productivity of industry. Better health education and interventions are therefore needed to help to start to deal with these issues. One starting point for the development of such interventions is to gain an understanding of how individuals think about and understand disease. There are long standing traditions in medical sociology as well as health psychology that have taken this approach (Calnan, 1987; Decruyenaere, Evers-Kiebooms, Welkenhuysen, Denayer & Claes, 2000; Hagger & Orbell, 2003; Helman, 1986; Leventhal, Leventhal & Contrada, 1998). However, this has not been applied directly to the area of occupational psychology. There are a few studies that have examined the perceived causes and nature of stress at work (Kinman & Jones, 2005). However, the nature of lay models is more extensive than simply the perception of causes (see below – Illness representations) and also it is not clear that ‘stress’ is in fact perceived as an occupational disease. One fundamental question that needs to be addressed is: what do people perceive to be occupational diseases. This leads to another important distinction: the difference in perceptions of 1 illness between lay and expert groups. It may be that diseases the lay public see as occupational may be different to those perceived to be occupationally related by relevant experts. In terms of the development of interventions and risk communications knowing about such differences will help translate resulting information into intervention tools in order to develop educational materials. A related issue that arises is one of trust in the source of communication. The role of perceived trust in risk messages is now widely acknowledged as an important dimension of risk communication (see Ferguson, Farrell, James & Lowe, 2004) and as such needs to be considered in other contexts where information on the type of disease, its causes and consequences are being discussed. This report sets out to provide the first ever study of how lay and expert groups represent occupational illness and looks for differences between the groups to examine perceptions of trust in information on occupational illness. The remainder of this introduction is structured around these themes.

1.1.3 Lay models of illness There are a number of ways that lay/expert models of illness have been explored in the literature (qualitative interviews, factor analysis of perceived causes, common sense models or illness representations and structural cognitive mapping) (Furnham, 1997; Helman, 1986; Kinman & Jones, 2005, Green & McManus, 1995; Moss-Morris, Weinman, Petrie, Horne, Cameron & Buick, 2002). Two of these approaches – illness representations and structural cognitive maps – are used in the research reported here (Green & McManus, 1995; Leventhal et al., 1998). The illness representation model was chosen for the following reasons: (1) it is the most widely used quantitative method, (2) there are reliable and validated psychometric tools available in the area (Hagger & Orbell, 2003; Leventhal et al., 1998) and (3) it has been used to compare the illness representations of patients and carers. The last point above, allows for certain predictions to be made about how experts and lay people may differ in terms of illness representations. This is based on the idea that patients are similar to experts (i.e., that they have good knowledge about their illness via experience) and carers are more akin to lay people (i.e., while having some experience of the illness this is less detailed than the patients). There are no current data on lay and expert groups from which to make more detailed hypotheses. Structural cognitive maps are chosen as the second model for the following reasons: (1) it is a new and innovative approach that allows for a pictorial representation of the interplay between causes of illness; (2) has been used to compare lay and expert representations of illness and (3) provides an opportunity for developing educational interventions (Green & McManus, 1995). A brief description of each of these approaches is provided below.

1.1.4 The illness representation approach This approach is designed to assess a person’s representation (understanding) of their illness along seven descriptive dimensions. These are described below.

1. Identity - the severity and type of symptoms the person believes define the disease. 2. Consequences –the perceived consequences of the illness on the person’s life (e.g., impact on the quality of life). 3. Time line – the perceived temporal pattern in the illness. That is, is the illness perceived as (1) chronic (e.g., stable over time and long lasting), (2) acute (e.g., short lived) and (3) cyclical (e.g., varies on a day to day/weekly basis). 4. Causes – the perceived causes of the illness (e.g., biological factors such as the immune system, psychological/emotional factors and environmental factors) 5. Cure – the extent to which the person believes that the illness/symptoms are controllable by medication or, indeed, if the illness can be cured. 6. Coherence – the person’s belief that they have a coherent understanding about the disease. This is similar to the idea of subjective knowledge: that is, what people believe they know rather than what they actually know about the disease (cf. Moss-Morris et al., 2002). In a sense it 2 assesses their perceived understanding. People may feel that they understand their illness, but their factual knowledge is incorrect. The role of subjective and factual knowledge is discussed later in this introduction. 7. Emotional Representation – the type of emotional responses people associate with their illness (e.g., worry, fear).

By gaining some knowledge/understanding of where people fall along each of these dimensions it is possible to make some predictions about their future illness related behaviours.

1.1.4.1 Illness representations and health related behaviours in patients The illness representations approach has been applied primarily to patients (and to a lesser extent carers) across a wide variety of illnesses (e.g., Addison’s disease, Alzheimer’s disease, atrial fibrillation, asthma, cancer, cervical abnormalities, chronic fatigue syndrome, chronic obstructive pulmonary disease, common cold, diabetes, HIV/AIDS, hypertension, irritable bowel syndrome, myocardial infarction, multiple sclerosis, muscular skeletal injuries, neuroepilepsy, osteoarthritis, psoriasis, recovery form oral surgery, rheumatoid arthritis and tuberculosis (see Hagger & Orbell, 2003 for reviews).

One main focus of this work has been to identify links between scores on each dimension described above and a variety of clinically relevant outcomes. These may be split into behavioural outcomes (e.g., coping, hospital attendance, compliance with treatment), emotional adjustment (e.g., anxiety/depression) and physiological measures (e.g., cholesterol levels). Work related outcomes have been reported rarely. Some of the typical findings are described below, drawing primarily on a recent meta-analytic review by Hagger and Orbell (2003).

Behavioural outcomes – With respect to coping behaviour typical associations in the literature are between perceiving the illness to be chronic (time line) and the impact on the quality of life (consequences) and the use of avoidance coping and denial. While people are more likely to use problem based coping strategies (e.g., making future plans) if they perceive their illness as controllable or curable, there is recent evidence that illness representation also influence attendance at clinics, with poor attenders more likely to see their illness are having more severe symptoms and as being less curable (Whitmarsh, Koutantji, & Sodell, 2003)

Emotional adjustment – Worse psychological distress was related to perceiving illness as chronic, with more severe symptoms and having a greater impact on the quality of life

Physiological outcomes – In patients (following their first myocardial infarction) there is some evidence to suggest an association between attribution to cholesterol as a cause of the MI and their actual cholesterol levels (Cameron, Petrie, Ellis, Buick, & Weinman, 2005). McCarthy, Lyons, Weinman, Talbot, and Purnell (2003) demonstrated that those who believed that what they did speeded their recovery (control/cure dimension) showed faster healing.

Work-related outcomes – A few studies have examined the role of illness representations and work related factors. Cameron et al. (2005) showed that patients who attributed their MI to cholesterol or eating fatty foods reported longer working hours. Lacroix (1991) has shown, with samples of patients suffering lower back pain or chronic respiratory symptoms, that those who have a less accurate interpretation of their symptoms returned to work later. McCarthy et al. (2003) reported that return to work following dental surgery was quicker for those who believed that their post-operative recovery would be quicker (time line dimension).

3 1.1.4.2 Illness representations and health related behaviours: The influence of carers/spouses Compared to the patient perspective work, much less research has examined illness representations from the perspective of carers or spouses. The work that has been conducted indicates that both spouse and carer illness representations influence patients (as well as carers) responses to their illness (Barrowclough, Lobban., Hatton., & Quinn, 2001; Heijmans, de Ridder & Bensing, 1999). For example, Heijmans et al. (1999) have demonstrated that spouses tend to view the patients illness more negatively than the patients. Patients see their illness as more curable, having fewer consequences and of a shorter duration. This discrepancy between patients’ and carers’ views had a negative impact on patients’ adjustment to their illness.

1.1.5 Structural Cognitive Mapping (SCM) The illness representation approach, described above, has been used to examine how single dimensions are related to a particular outcome (e.g., hospital visits). While the dimensions studied are correlated with each other, this approach does not aim to look at this inter-relatedness as a way of understanding people’s models of the causes of their disease or motivators for action. A recent development has been the use of structural cognitive maps (Green & McManus, 1995) which aim to incorporate the principles of structural equation modelling with fault tree/network style analysis. An example is given in Figure 1 and will be used to illustrate this technique.

+ve Diet Physical injury +ve +ve +ve

Environmental Alcoholism +ve Liver Disease factors

+ve +ve +ve +ve +ve

Genetics Infection

Stress +ve

Figure 1 Example of a structural cognitive map

In structural cognitive mapping a set of initial predictor constructs are derived from interviews or the literature. So for example, if the outcome of interest is liver disease a list of potential causes would be identified. People are then asked to construct a map of relationships between the potential causes and the outcome as well as between the causes. They assign a value to the link – usually between 0 and 100 – to indicate the extent to which the predictor is a cause of the outcome (large values mean that it is a 4 stronger predictor denoted by thicker arrows in figure 1). Finally, participants indicate if the relationship is a beneficial one (reduces the risk – usually denoted with a negative) or detrimental one (increases the risk – usually denoted with a positive). Scores are aggregated across participants to produce a group level representation using procedure derived from structural equation modelling. This technique allows a fuller representation of proximal and distal causes and those causes that are perceived as the most important. For example, alcoholism is perceived in Figure 1 as the most important cause of liver disease. However, both stress and genetic factors are seen to predict alcoholism – with stress as a distal indirect cause as it is not directly linked to liver disease. Diet is perceived as a smaller direct effect on liver disease but is it self directly influenced by alcohol. This technique has been applied to a number of different outcomes including heart disease (Green & McManus, 1995) and unemployment (Green, McManus, & Derrick, 1998).

This technique does not include all of the dimensions incorporated in the illness representation model, but focuses primarily on causes. However, it does offer an important tool for developing education interventions (see below) and should be used in conjunction with a more structural technique such as illness representations.

1.1.6 Lay models limitation and applications to occupational disease To date, lay models have not been applied directly to the issue of understanding occupational illness. The main limitations, issues, directions for research and rationale for looking at lay models of occupational illness are detailed below.

Little current directly relevant research – Some recent work examining the causal dimension of occupational stress (Furnham, 1997; Kinman & Jones, 2005; Rydstedt, Devereux & Furnham, 2004) exists. However: (1) it is not clear that occupational stress is an occupational illness and (2) this work only examined causal dimensions of stress and did not explore other factors (e.g., identity, time line etc). Further, there is some other work which shows that patients do attribute their cardiac disease to stress (including work stress) (Calnan, 1987; Cameron et al., 2005). However, this is not to say that their heart disease can be classified as an occupational illness. Therefore, at present there is no information on what the lay public class as occupational illnesses, what they think causes them, what they believe their time line is, what they imagine their consequences are etc.

Expanding the illness representation model – The causal dimensions assessed in illness representation models do not refer to working conditions. Thus it is not clear the extent to which working life is seen to contribute to illness that might be classified as occupationally caused (e.g., asthma) or not occupationally caused (e.g., multiple sclerosis).

Exploring healthy individuals & developing interventions – From the work on carers and spouses it is known that they hold their own illness representations which are different to those of patients and that these representations influence self and patient outcomes. It can therefore be asked: do the general public hold particular views about the role of work in a variety of illnesses and perceive some illness as more likely to be attributed to work. Knowing how the general public thinks about the role of work in illness will help to identify potential educational interventions and communications in relation to the relevant illnesses, especially by comparing healthy individuals to experts who might be directly responsible for treating them (see the main section below on experts versus novices and the development of interventions).

5 1.1.7 Other factors that influence illness representations

1.1.7.1 Risk perception and knowledge The way in which people understand illness in terms of its causes, symptoms, controllability, prognosis, and time course is likely to be influenced by an individual’s perceptions of risk relating to that illness. In turn, information about the illness can inform the degree to which a person believes themselves to be at risk. For example, if a person believes that smoking cigarettes is a major cause of lung cancer, and they smoke, it would appear sensible to assume that they are more likely to believe that they are at risk from developing lung cancer. However this may not necessarily be the case, and the literature on the relationship between knowledge about illness and the way in which people perceive themselves (a) to be at risk from that illness; and (b) adapt their behaviour in a health-promoting manner is equivocal (cf. Ferguson, 2001).

For a person to be protected from a potentially harmful outcome, they need to be firstly aware that there is a risk of harm and know what behaviours can either prevent them coming into contact with the hazard or protect themself from the impact the hazard will have on their health. The knowledge deficit model assumes that the there is a gap between ‘expert’ and lay knowledge about a disease or illness and that by closing that gap – by educating the lay public about the causes, and prevention of the disease, the lay public will behave in a more health protective manner (Ferguson, 2001). Such work has typically focused on groups believed to be ‘at risk’ from illness or disease. For example, Marrazzo, Coffey and Bingham (2005) showed that knowledge about the transmission of STIs (Sexually Transmitted Infections) amongst lesbian and bisexual women was typically low resulting in sexual behaviours likely to increase levels of bacterial vaginosis such as not washing sex toys or hands. Further, Arslanian-Engoven (2005) examined the beliefs and levels of knowledge amongst black, hispanic and white women in relation to symptoms of myocardial infarction. The results showed that amongst hispanic women, there was a common belief that having a headache was a symptom, which could potentially lead to increases in health anxiety and possible non-recognition of a serious health condition.

However, studies examining expert, lay and patient groups have shown that knowledge and risk perception may be not be related. For example, Adam and Reyna (2005) showed that experts with specialisation in adolescent STI education had a high degree of knowledge about the diseases and the ways of preventing contagion. However, this knowledge was not related to the way in which they perceived the extent to which condoms reduced the risk from contracting an STI. Specifically, the experts in their sample tended to over-estimate the effectiveness of condoms. Additionally practitioners working within the area of diabetes care had high levels of knowledge about the lifestyle factors associated with the disease but this was not related to perceived personal risk of developing diabetes. Rather optimistic bias appeared to be operating for this group (Walker, Kalter, Mertz & Flynn, 2003).

Similar patterns have been found with patient groups and amongst individuals with a close family member living with a disease. Werner, Olchovsky, Erlich-Gelaki and Vered (2003) demonstrated that knowledge about osteoperosis did not differ between women who had a close family member with the condition, and those without it. However, those who had a family member with osteoperosis not only considered themselves to be at higher risk of developing the condition, but they also attended screening more and had greater concerns about developing the condition. Finally, research examining the behaviour of those deemed ‘susceptible’ to various health risks has also indicated that knowledge and behaviour may not be directly related. McLennan’s (1998) study of diarrhoea prevention in developing countries showed that whilst 90% of the sample knew that hand-washing helps to reduce the chance of infection by removing harmful bacteria and parasites, only 65% of the sample practiced the behaviour. In addition, Haldiya, Sachdev, Mathur and Saiyed’s (2005) examination of the health practices of salt 6 workers in India reported good levels of knowledge about prevention of work-related hazards, 70% typically did not use any preventative measures.

It is likely, therefore, that other factors mediate or moderate the relationship between knowledge and behaviour. For example the extent to which individuals trust the information about disease or illness may make them more or less likely to act in a health promoting fashion (Alaszewski, 2005; Ferguson, 2001; Emmett, & Ferguson, 1999; Ferguson et al., 1994). Hoevenaars, Schouten, Van den Borne, Beckers, and Webers (2005) illustrated this point by showing that individuals with glaucoma preferred to use the knowledge about the disease communicated to them via nurses or ophthalmic practitioners – and especially if this information was in written form. However, other studies have shown that the degree to which individuals trust a source of information is generally unrelated to their perceptions of risk. Ferguson, Farrell, James and Lowe (2004) for example indicated that those involved in the blood transfusion cycle (blood donors, anaesthetists, GPs etc) typically showed an optimistic bias regarding receiving blood via transfusion rather than being influenced by the trustworthiness of the source of information.

In terms of knowledge, a distinction may be drawn between factual knowledge and evaluations of a person’s individual knowledge. Factual knowledge is assessed in terms of answers to multiple choice questions (MCQs). Evaluations of knowledge may be assessed by asking participants to provided judgments about the perceived accuracy of (i.e. confidence in) each of their answers to MCQs. Knowledge calibration can also be calculated by comparing the degree of actual accuracy (that is, percentage correct) with the perceived level of accuracy (confidence). A positive coefficient indicates over-confidence (participants think they know more than they actually do), a negative score indicates under-confidence (participants know more than they actually think the do) and zero indicates perfect calibration (participants know what they think they know).

In general, the evidence does not support the premise that factual knowledge is related to perceptions of risk (Ferguson, 1996). Furthermore, recent work on transfusion risk showed that it was evaluations of knowledge and not factual knowledge that was related to perception of personal risk from transfusion (Lowe & Ferguson, 2003; Ferguson et al., 2001; Ferguson et al., 2004). Therefore, in the work reported here, we assess factual knowledge, subjective knowledge and knowledge calibration.

1.1.7.2 Trust in Information The news media (Brown, Chapman & Lupton, 1996; Lebow, 1999) and information presented by professional organizations (Eiser, Miles & Frewer, 2002) represent two key sources of information that have been most consistently studied with respect to perceptions of risk. Less attention, however, has focused on studying the relationship between trust in different sources of information (e.g. TV, newspapers, internet) and perceived risk (see Ferguson et al., 2004, Irving et al., 1997 for an exception). However, evidence from the general literature on trust and risk suggests that higher levels of trust in, for example, organizations or consumer bodies, are associated with lower levels of perceived risk (Frewer, Howard, Hedderley & Shepherd, 1996; Siegrist, 2000; Eiser, Miles & Frewer, 2002). Following Ferguson et al (2004) and Irving et al (1997) a wide variety of sources of information were examined (internet, HSE, government etc).

1.1.8 Expert-novice divide and the development of educational interventions Within the domain of health and occupational health, patients (lay people), medics (experts) and public health promoters (experts) may have very different models of an illness; its causes, time-line, cure, or consequences. This may in turn influence how they present relevant information to each other. With different models it may be difficult to communicate the appropriate information. As such, identifying such discrepancies will help in the development of education programmes. It is of note that to date no 7 comparison of expert and novices (lay public) has been conducted in the domain of occupational health and none using the illness-representation approach. One study has been conducted using structural cognitive maps (Green & McManus, 1995). This section will briefly review how experts and lay representation may differ and then draw conclusions on how this can be applied to the domain of occupational health and the development of educational programmes.

1.1.8.1 Lay versus expert representations Early research into expert behaviour tended to look at problem solving skills in limited domains (e.g., chess). De Groot (1965) found that skilled chess players did not search ahead for a good move more than the less skilled players, rather as shown by Chase and Simon (1973) expert chess players are better than novices because they know and recognize more patterns of pieces than the novices. They claimed that experts' 'chunks' of information are richer than novices', permitting better recall. This has several consequences for expert behaviour. First, experts often recognize the key features of a domain. Second, this in turn allows experts to be selective in applying their knowledge to a problem situation. Third, as Klein (1998) has suggested, in some domains such as nursing and fire-fighting experts might explore only one option.

At the same time, research has also indicated that expert schemas are qualitatively different from those of non-experts (Feltovitch & Barrows, 1984; Koedinger & Anderson, 1990). In the case of medical expertise, for example, schemas may represent both clinical knowledge (for example, how a particular disease may be associated with particular symptoms) and biomedical knowledge (how the disease process leads to those symptoms). These schemas can be used by medical experts to filter out irrelevant information and focus on the key elements of a medical problem (Patel, Arocha & Kaufman, 1994; Patel & Kaufman, 1995). Lesgold et al. (1988) have studied physicians’ abilities to read x-rays. Using x-rays to diagnose a collapsed lung (atelectasis), radiology interns (novices) knew the general set of symptoms that indicated atelectasis, but were unable to deal with difficult cases where one or more of the indicators were missing, or indicators for other diseased states present. The expert radiologists, although possessing schemas that were general in application, also possessed schemas with more specific applications. Once a possible diagnosis state was recognized using a generalized schema, more specific schemas were utilized, taking account of the information that novice radiologists found so hard to use. Experts and lay people then can be expected to differ in two substantive ways. First experts know a lot more and secondly, that knowledge is organized more effectively for experts.

1.1.8.2 Assessing lay and expert knowledge One method of accessing lay perceptions has been to adopt the network analysis approach (Antaki, 1988). In this technique, participants in the research consider how a number of supposed causes of a particular outcome can be considered causes of that outcome or of the other causes presented. Criteria are then adopted to decide which causal links should be included in a ‘network diagram’. This technique has been applied to a diverse selection of domains, including: student political action (Antaki, 1989); crime (Campbell & Muncer, 1990); unemployment (Green, McManus & Derrick, 1998); and reasons for wanting a child (Langdridge, Connolly & Sheeran, 2000). Within the field of health this technique has been applied to such outcomes as heart attacks (French, Marteau, Senior & Weinman, 2002), coronary heart disease (Green & McManus, 1995), work-related stress (Muncer, Taylor, Green & McManus, 2001), and lower-back pain (Campbell & Muncer, 2005).

Green and McManus (1995) used a particular version of this technique that involved asking participants to draw the connections between putative causes of heart disease and to rate the strength and direction of the relationship. They found, for example that undergraduate students with and without medical training differed to some extent in the connections between the causes. Whilst, second 8 year medical students cannot be expected to be classified as experts their increased knowledge of the domain did lead to a structurally different representation of the causes of coronary heart disease. At the same time there was a great deal of similarity between the two causal models that were generated by the network analysis. Shaw(2002) has argued that perhaps we should not be surprised by the similarity between medical and lay models of specific health problems since medical discourses permeate western culture. He suggests that patients and lay people frequently adopt the professional’s discourses and explanations. This is not unreasonable since the medical expert is expected to have skills and knowledge that the lay person does not possess.

Taken together, research on experts and lay people suggest that we can expect to find differences in both the amount of knowledge and the structure of that knowledge. However, using network analysis to access the structure of that knowledge we should also expect a large degree of similarity between expert and lay causal models of occupational health problems.

1.1.8.3 Expert and lay models in occupational health Within the domain of health the “expert” has often been the text book. So, lay models of illness have been compared to the causes as ascribed in text books in terms of the standard medical model (cf. Furnham, 1988). Within the context of occupational health the only assessments based around illness representation have focused on the causes of occupational stress (e.g., Kinman & Jones, 2005). Again it is not clear that this is an occupational illness and, again, only causes are looked at.

Furthermore, when the lay public think about expertise they may think about experts as categories of people who might not agree with each other and the advice they provide changes over time. Again this emphasises why it is important to collect data on perceived trust in sources of information. While there may well be differences between lay and expert groups in terms of illness representations or the nature of structural cognitive maps, the extent to which different groups are perceived as trustworthy may account for some of these differences.

Development of Educational Interventions By exploring differences between lay and expert groups a better understanding of how to develop educational interventions and guide communication strategies, can be gained (see Ferguson et al., 2004). For example, Ferguson et al (2004) compared levels of knowledge (calibrated and raw), perceptions of risk and trust in sources of information in lay and expert groups involved in blood transfusion. These authors argued that it is necessary to explore lay and expert groups – to identify similarities and disparities – as these two groups form the key stakeholders when negotiating treatment options. These groups differed with respect to the type of information they saw as trustworthy (e.g., experts more likely to rate scientific sources as trustworthy; lay participants more trusting of popular sources such as friends/newspapers). Similarly within the scope of the current study differences between expert and lay groups should provide valuable information. For example, do lay and expert groups differ with respect to whether or not they see work as a cause of different illnesses some of which are traditionally seen as work-related (e.g. stress) and others that are not (e.g. multiple sclerosis). If there are differences here then both groups – and especially the experts need to know this – so as to better aid communication. The same will be true of trust in sources of information. If the lay public do not trust the HSE or Occupational Health Physicians then information presented by these sources may be less effective. Knowing this means that steps can be taken to improve trust, and identify when risk communication from these sources may be less likely to be effective.

9 1.2 CONCLUSIONS AND STUDY QUESTIONS

This programme of research will aim to answer the following five questions. 1. What diseases/illnesses do people (experts and the lay public) class as occupational? For example, do the lay public categorize stress as an occupational disease, in the same way as other occupational diseases (e.g., causes, curability, time course) for which there are medical/physiological markers (e.g., occupational asthma)? • This will be explored using interviews with lay and expert people and with the use of survey methods, where participants will be asked about their understanding of cause (occupational or otherwise) of diseases that vary with respect to the extent that they are potentially occupationally caused. 2. What factors do people (expert versus lay) perceive as causing occupational diseases? This question is directly related to [1] above. In [1] we ask are certain diseases more likely to be seen as caused – to a greater of lesser extent – by occupational factors. The question here then becomes about what other factors (work and non-work related) distinguish the types of disease. • This will again be assessed via survey (field based experiments) and the use of cognitive mapping. 3. What are the main sources of trusted information about disease, occupational or non occupational? Do these vary by disease type? What is the relationship between trust in sources of information and illness representations? • This will be assessed via the field based experimental survey. 4. Are people (expert versus lay) under- or over-confident with respect to their knowledge about occupational and non-occupational related diseases? To what extent is the degree of knowledge calibration related to illness representation factors? • This set of questions will be addressed the field based experimental survey. 5. Do experts and the lay public have similar models of occupational and non-occupational disease and symptoms? For example, experts may perceive certain diseases as having a different time line or occupational consequence than lay people? Such disparities are important to know about in terms of public health (Hunt et al, 2001). As such, understanding points of comparison and disparity for lay and expert samples is important for the development of education and training. • This question will be addressed the via the field based experiment al survey and the cognitive structural mapping study.

1.3 OBJECTIVES OF THE PROJECT

The main objectives of this research programme are to identify o the types of diseases that lay and expert samples see as occupationally determined o the sources of information about occupational disease that are seen as trustworthy, and how this varies by expertise, o points of congruence and disparity between experts’ and novices’ models of occupational disease that can, in turn, be used to develop educational and training interventions.

10 1.4 MAIN DELIVERABLES OF THE PROJECT

The main deliverables will be: o a description of how people (lay and expert samples) structure their knowledge and beliefs about occupational disease, their trusted sources of information and how these are inter-related, o This will be derived from the interviews survey and cognitive structural maps as it relates to the aims and objectives and will form the main analytic aspects of the report. o a generic methodology for assessing lay and expert models of occupational disease which can be used in relation to any occupational disease, o This will be described in brief at the end of the report with reference to specific chapters and consist of guidelines on how to develop and use similar materials for other diseases in terms of illness representations as well as how to conduct and analyse cognitive structural maps. o a means for translating differences between lay and expert models into training and educational materials, o Again this will be described at the end of the report in the appendices and consist of guidelines on how to thinks about interactions that take advantage of differences between lay and expert groups. o feedback and commentary from lay and expert groups on the models o Once the final models have been developed from the cognitive maps, the expert and lay groups will be asked to provide a brief commentary on these models in terms of the accuracy and educational implications. The educational implications will be used as part of the process for developing the educational materials described above. o a generic method for developing measures of knowledge about disease o Again in appendices we will describe in brief a methodological process for developing simple knowledge items.

1.5 THE STRUCTURE OF THE REPORT

This report will be structured around the main research questions posed above. A separate chapter will be devoted to each. Prior to discussing each of these questions the next chapter will detail the methods, samples and materials used to address these questions.

11 2 METHODS, SAMPLES AND MATERIALS

Two pilot studies were conducted which were used to develop material for the 3 main studies. A final small scale cross-validation study was completed.

Pilot Studies

1. Pilot for Disease Types 2. Pilot for the National Randomised Field Based Study

Main Studies

1. Lay and Expert Interviews 2. National Randomised Field Based Study & Targeting of Experts 3. Expert and Lay Cognitive Mapping

Cross Validation Study 1. Cross-Validation Study

This chapter will detail the pilot work and how it was used to develop the materials for the main studies. The sampling procedures and methods for the 3 main studies and the cross validation studies will then be described. The subsequent chapters will detail the results from the main studies as they pertain to the main research questions addressed by this research.

2.1 PILOT STUDY 1: PILOT OF DISEASE TYPES

2.1.1 Aim of the Study The aim of this study was to identify the types of diseases that people view as occupationally determined. Measures of participants’ perceptions of disease aetiology were taken to identify a selection of diseases/disorders to be explored in the main interview study of lay and expert participants. The purpose of Pilot Study 1 was therefore to generate a sample of 9 diseases from a wider list of 20, according to subjects’ perceptions of whether these diseases had work-related origins. The results of this study are described in Chapter 3.

2.1.2 Method

2.1.2.1 Procedure Participants were asked to rate, on a 10 point Likert-type scale, to what extent they believed each disease was caused by work, from 0 ‘not at all’ to 10 ‘entirely’. See appendix 4 for copy of questionnaire. Participants were volunteers and were assured of confidentiality and anonymity.

2.1.2.2 Participants 52 participants (29 female) completed the brief questionnaire. Mean age was 36 years (range 18-60). Subjects were classified by occupation as ‘lay’ or ‘expert’. ‘Expert’ participants were defined as those having some knowledge or experience of occupational disease: e.g., occupational therapists, medics, occupational and health psychologists. The majority of subjects (72%) fell into the ‘lay’ category.

12 2.1.2.3 Measures 20 diseases/disorders were included on the questionnaire. Diseases were selected according to their status as prescribed occupational diseases under the RIDDOR Regulations (1995). 10 diseases were reportable under these regulations, and 10 were not. The 10 reportable diseases were selected to include a sample of conditions due to (1) physical agents and physical demands of work (hand/arm vibration syndrome, carpal tunnel syndrome), and (2) infections due to biological agents (tetanus, tuberculosis), cancers (lung, bone), asbestosis, bronchitis, dermatitis and asthma. 8 diseases not described in the RIDDOR Regulations as occupational diseases were approximately matched for disease type (i.e. infections, cancers). These were: leukaemia, multiple sclerosis, measles, stomach cancer, coronary heart disease, hernia, chronic fatigue syndrome, and shingles.

Stress and back pain were also included in the questionnaire, as these are both accepted as major causes of work-related absence. Back pain is classified as an injury and therefore not included under the regulations as a prescribed ‘disease’. Stress is a mental state and therefore specifically excluded from RIDDOR, but is also often cited as a major cause of work-related absence and was therefore included in the questionnaire. The incidence rates of the prescribed occupational diseases included on the list varied from 0 in reporting year 2002/2003 (bone cancer) to 666 (hand/arm vibration syndrome). These figures are those reported under the RIDDOR regulations and therefore are only reflective of those cases that were determined to be work-related.

2.1.2.4 Overview of the target-disease selection process Figure 2 shows diseases selected at different stages of Pilot Study 1 and Main Study 1. From the 20 diseases originally examined in Pilot Study 1, target diseases for all other studies in the research were derived. Pilot Study 1 was used to group 20 diseases into 3 clusters according to work-relatedness: (1) highly occupational, (2) ambiguous, and (3) non-occupational. From each of these clusters, diseases with the top, middle, and bottom ranking mean-scores were selected for examination in the interview study (Main Study 1). This step yielded a selection of 10 (rather than 9) diseases, as 2 diseases in the ‘highly occupational’ cluster had equal (top ranking) means: stress and asbestosis. Initial data collection for Main Study 1 indicated that there would not be time to discuss 10 diseases in each interview session. In response to this time constraint, the number of target diseases in Main Study 1 was reduced from 10 to 6 by selecting only the top and bottom ranking items in each cluster (Pilot Study 1). Stress was finally preferred to asbestosis in the revised selection of 6 diseases for Main Study 1 (for reasons discussed in section 3.2.1).

Feedback from expert- and lay-participants in Main Study 1 was used to select 4 target diseases for the final studies of the research (Pilot Study 2, Main Study 2, and Main Study 3). Three of these 4 diseases were taken from the 6 that were specifically explored in Main Study 1; the fourth (asthma) was added from the original list of 20 diseases following expert comments in the interviews. The rationale for the final selection of 4 diseases is presented in section 2.3.1.1.

13 Figure 2 Overview of disease selection process across Pilot Study 1 and Main Study 1

2.2 MAIN STUDY 1: LAY AND EXPERT INTERVIEWS

2.2.1 Aim of the Study Semi-structured interviews, conducted by telephone or in person, were used to assess participants’ categorisation of a number of pre-selected diseases (derived form Pilot Study 1). Perceptions of the causes, symptoms, treatment, and time lines of these diseases were explored.

The aim of this study was to collect more in-depth data on lay and expert categorization of both occupational and non-occupational diseases. Of particular interest were the industries they perceive as having high and low risk of occupational disease; perceived causes and symptoms of these diseases, their time lines, cures and consequences. Information obtained from participants during these interviews was used to help determine which illnesses were the focus of the large scale national random survey of 12,000 members of the lay public, and was used to guide the development of questionnaire items for this survey. As such this interview study was seen as a detailed piece of pilot work rather than a definitive qualitative study.

2.2.2 Methods

2.2.2.1 Participants 21 experts and 19 lay people were interviewed for the study. Lay participants were recruited by placing adverts around the university campus. The lay sample included various non-health related occupations (e.g., accountant, financial advisor, project manager, health economist, catering supervisor, placement officer, professor of economics, secretaries). Expert participants were recruited from a variety of sources. Participants were identified through ALAMA, an association for public sector occupational health physicians; the occupational health service at the Queen’s Medical Centre, business health care contacts through network sampling, and occupational psychologists through the British Psychological Society. Expert participants include: occupational health consultants, specialist registrars, occupational health physicians, occupational health nurses, nurse specialists and nurse consultants, chief medical officers for large corporations, a stress counsellor, and occupational psychologists.

14 The minimum years work experience for experts was 5 years, maximum was 36 years; mean work experience was 18 years. The minimum years work experience for lay people was 1 year, maximum was 35 years; mean work experience was 12 years. 87% of all participants had never suffered from a work related illness. Half of all participants, however, knew someone who had suffered from a work related illness (50%).

2.2.2.2 Interview Schedule The interviews were semi structured and were developed using Leventhal et al’s (1998) illness representations model (see appendix 4 for full interview schedule). Topics included: • Causes of the disease – beliefs about factors associated with illness onset. • Symptoms of the disease – including consequences of these symptoms in terms of quality of life. • Timeline of the disease – the course of the illness. • Control of the disease – including treatment available, prevention, and control of illness progression. • Incidence of the disease – including an estimate of the proportion of occupationally determined cases amongst total cases. • Industries with a high prevalence of the disease.

Six diseases were discussed in terms of participants’ perceptions of their causes, symptoms, treatments, timeline, incidence and prevalence in the workplace (this number was reduced from the 10 identified in Pilot Study 1 after further pilot interviews due to time constraints). The six diseases were originally chosen on the basis of results from Pilot Study 1. Diseases with the highest and lowest means from the following three clusters were included in the interviews: Non-occupational: multiple sclerosis, lung cancer; Highly-occupational: carpal tunnel syndrome, stress; Ambiguous: tetanus, hernia.

2.2.2.3 Procedure The interviews were semi-structured. No prompting was given, although participants were encouraged to expand on points of interest. Participants were asked about each disease in turn, and the order in which each disease was presented was rotated between participants. Interviews lasted between 20 to 90 minutes. Participants were told in advance that interviews would be expected to take around 30 minutes. As some experts had much to say on some of the illnesses, they were given the option to finish after 30 minutes even if some illnesses had yet to be covered. Therefore, several (70% of total) participants completed fewer than the six illnesses. The remainder of participants were happy to complete the full interview, even if this meant running over time. Most interviews were conducted face-to-face, although some were conducted by telephone. Most participants agreed for their interviews to be tape recorded.

2.3 PILOT STUDY 2: PILOTING & DEVELOPING THE QUESTIONNAIRE MATERIALS TO BE USED IN THE RANDOMISED FIELD STUDY

Data from the interview study was obtained primarily to aid the development of the questionnaire to be used in the large-scale random survey. The questionnaire was based on Moss-Morris et al’s (2002) Illness Perceptions Questionnaire (revised) (IPQ-R), with items added on the basis of analysis of the interviews.

15 2.3.1 Developing the questionnaire

2.3.1.1 Illnesses 4 illnesses were chosen based on the previous studies. They are lung cancer, asthma, stress and multiple sclerosis.

• Stress was chosen because of its strong association with work by the lay sample. Stress was also identified as having a wide range of symptoms, which, unlike most of the other illnesses, can be not only physical but also behavioural and psychological.

• Lung cancer was chosen because it can have work-related causes, but because of its long latency period these can be hard to determine with any certainty. It has easily definable symptoms making it easy to diagnose.

• Asthma was chosen for inclusion in the study. Although asthma was not a disease explored in the interviews (Main Study 1), it was highlighted by the experts as being a common occupational illness that, unlike lung cancer, is relatively easy to identify as work-related. Symptoms of occupational asthma can come on immediately on exposure to harmful substances, therefore providing a contrast to the long latency of lung cancer. Symptoms of asthma are also relatively easy to define. In addition, asthma may have both work and non work-related causes.

• Finally, multiple sclerosis was chosen as this was an illness identified definitively by both lay and experts as having no work-related cause.

2.3.1.2 Symptoms A frequency count of reported symptoms was taken for each of the diseases from the interviews. 14 of the symptoms reported are also on the IPQ-R. These were: (1) pain, (2) sore throat, (3) nausea, (4) breathlessness, (5) weight loss, (6) fatigue, (7) stiff joints, (8) sore eyes, (9) wheeziness, (10) headaches, (11) upset stomach, (12) sleep disturbances, (13) dizziness and (14) loss of strength. For each disease, additional symptoms were identified from the interviews. Participants were not prompted to offer any specific symptoms – therefore all specific symptoms were generated spontaneously. Frequency counts (presented in parentheses) for each disease were as follows (IPQ items in normal font, additional items in italics): Carpal Tunnel Syndrome: Pain (22), pins and needles (12), loss of circulation/numbness (5), stiffness (1), loss of mobility (5) and loss of grip (9). Hernia: Pain (27), breathlessness (1), upset stomach (2), sleep disturbances (1), protusion/swelling (18), difficulty with movement (1). Tetanus: Pain (3), breathlessness (2), weight loss (1), fatigue (1), upset stomach (1), loss of strength (1), muscle spasm (5), paralysis (1), fever (3), jaw stiffness (11). Stress: Pain (2), nausea (1), breathlessness (2), weight loss (1), fatigue (15), headaches (11), upset stomach (6), sleep disturbances (15), anxiety (16), appetite disruption (7), inability to cope (5), sweating (5), palpitations (5), depression (15), irritability (11). Multiple sclerosis: Pain (5), fatigue (8), headaches (1), dizziness (2), loss of strength (8), difficulty walking (17), balance problems (6), speech problems (5), cognitive problems (3), pins and needles (5), numbness (6), visual disturbance (11). Lung Cancer: Pain (18), breathlessness (30), weight loss (7), fatigue (7), wheeziness (1), loss of strength (4), cough (27), malaise (2), loss of appetite (2).

16 To develop the questionnaire, the two most frequent symptoms from each of the three relevant diseases were included, along with two symptoms common to all six diseases. Finally, two additional symptoms were added from the IPQ-R which had high frequency counts in the interviews. The symptoms included in the questionnaire were: (1) anxiety, (2) cough, (3) depression, (4) decreased mobility, (5) breathlessness, (6) fatigue, (7) pain, (8) visual disturbance, (9) headaches and (10) sleep disturbances.

2.3.1.3 Illness representation dimensions Items from the IPQ-R were adapted to measure timeline (acute/chronic, cyclical), control (treatment and personal), consequences, illness coherence, and emotional representations. The top two loading items from each category derived from a principal components analysis of the IPQ-R items (Moss- Morris et al. 2002) were used where appropriate. These items were adapted to reflect participants’ beliefs about what it would be like if they had the disease – that is, the measure was adapted in a similar way to those that have been adapted for carers/spouses. Most of the items relating to cause were included from the IPQ-R. Additional items were added to include work related causes (e.g., work load). Additional items were added which were derived from the interviews. These include items relating to employers’ responsibilities for prevention/protection against illness and the work-related consequences for an employee with the illness.

2.3.1.4 Sources of information These items were developed using data from the interviews (Main Study 1). Interviewees were asked who they would trust to provide them with information about occupational diseases. The most frequently reported sources were included in the questionnaire. These were: (1) GP (frequency = 14), (2) internet (frequency = 8), (3) HSE (frequency = 7), (4) employer (frequency = 3), (5) friends/family (frequency = 5), and (6) occupational health (frequency = 7). Newspapers/magazines and television were also included.

2.3.1.5 Knowledge items These multiple choice items were included to test people’s objective knowledge of matters relating generally to the illness in their questionnaire – for example, questions on respiration for lung cancer and asthma, questions on the central nervous system for multiple sclerosis. Two questions specific to the illness are included, with one further question common to all illnesses. All questions (and appropriate answers) were obtained via the British Medical Association web-site. Respondents were also asked to rate how confident they were that their answer is correct for each question on a 4 point scale from 1 not confident to 4 extremely confident.

The following illness-specific questions were administered in the MS questionnaire: The Central Nervous System is made up of the a) liver and kidneys b) heart and lungs c) brain and spinal cord d) stomach and intestines The primary cells of the nervous system are called a) synapses b) neurones c) platelets d) muscles

The following (respiratory) illness-specific questions were administered in asthma and lung cancer questionnaires: The average lung capacity of a healthy adult is a) 1 litre b) 2 litres c) 5 litres d) 10 litres What is the average number of breaths per minute of a healthy adult? a) 5- 10 breaths b) 15-20 breaths c) 25-30 breaths d) 35-40 breaths

The following illness-specific questions were administered in the stress questionnaire: 17 When a person is under excessive stress, the body can produce a chemical called a) adrenalin b) progesterone c) sodium d) chlorine

Which illness is stress most likely to cause? a) eczema b) heart disease c) asthma d) appendicitis

The question common to all illness questionnaires was as follows: For a healthy adult, what is the average range for resting pulse rate (beats per minute)? a) 20-60 bpm b) 40-80 bpm c) 60-100 bpm d) 80-110 bpm

Apart from the knowledge items discussed above, the final questionnaires were identical for all four illnesses, with only the illness name changed throughout. See appendix 4 for final versions of all four questionnaires.

2.3.2 Piloting the questionnaire The newly developed questionnaires were piloted on a small sample in order to identify potential problems and make amendments before sending it out to 12,000 people. All four versions of the questionnaire (asthma, multiple sclerosis, lung cancer and stress) were piloted.

2.3.3 Methods

2.3.3.1 Participants 111 psychology undergraduates and postgraduates at University of Nottingham and City University, London, with a mean age 23 of years (min. 19 years, max. 47 years) completed one version of the questionnaire [Multiple Sclerosis, n= 28; lung cancer n=22; stress n=30; asthma n=31]. Of those who indicated their sex, 78 were female, 21 were male. 86% of all participants had never suffered from a work-related illness. Only 3 % had suffered from an occupational illness. The remaining participants did not respond to this item. 21% of all participants, however, knew someone who had suffered from a work related illness.

Participants were asked whether they had suffered from or knew anyone who had suffered from the illness relevant to their questionnaire. None of the participants had suffered from MS or lung cancer, however, 40% of participants knew someone with MS, and 18% knew someone who had suffered from lung cancer. 37% of participants reported that they had suffered from stress. Of these, 17% said that they had taken time off because of their stress experience. 70% of participants knew someone who had suffered from stress. Finally, 23% of respondents suffered from asthma, with 87% knowing someone who suffered from asthma. Thus stress and asthma have the highest reported frequencies.

2.3.3.2 Measures All four prototype versions of the questionnaire developed through the interview study were used.

2.3.3.3 Procedure Participants were recruited during lectures. It was made clear that participation was voluntary and that all responses would be anonymous and confidential. Participants were asked to complete the questionnaire, and also to add any comments, as it was stated that this was a pilot study and comments on specific questions would be welcome.

2.3.4 Results The data were examined to check the questions were appropriate, to explore the distribution of responses to all items, and to take a preliminary analysis of the data. 18 2.3.4.1 Symptoms and illness identity Participants were asked to indicate whether they thought that a person with the relevant illness would experience the symptoms presented in Table 1. Results showed that there were significant differences in the level to which participants thought the symptoms would be experienced between illnesses, for all symptoms apart from anxiety and sleep disturbance. Table 1 shows the F ratios, descriptive statistics, and significant differences between illnesses (post-hoc comparisons using Tukey’s HSD).

Table 1 Table to show means (and standard deviation) for presence of symptoms by illness

Multiple Significant Symptoms F Sclerosis Lung Cancer Stress Asthma differences Anxiety 2.22 3.5 (1.2) 4.1 (1.1) 3.9 (.94) 3.3 (1.0) LC > MS LC > S Cough 20.56*** 1.8 (1.5) 4.2 (1.1) 1.7 (1.3) 3.3 (1.3) A > MS A > S MS > A Depression 10.60*** 3.6 (1.4) 3.3 (1.3) 3.4 (1.0) 2.0 (.98) LC > A S > A MS > LC Decreased mobility 22.03*** 4.4 (.80) 3.3 (1.2) 2.0 (1.4) 2.2 (1.1) LC > S LC > A LC > MS LC > S Breathlessness 24.02*** 3.0 (1.3) 4.4 (.60) 2.3 (1.5) 4.2 (.71) A > MS A > S Fatigue 4.17** 4.1 (1.0) 3.8 (.89) 3.4 (1.3) 3.1 (1.2) MS > A LC > A Pain 15.18*** 4.0 (1.2) 4.0 (.94) 2.0 (1.3) 3.0 (1.1) MS > A A > S MS > LC Visual disturbance 5.12** 2.9 (1.4) 1.8 (.93) 2.1 (1.2) 1.8 (1.1) MS > A S > MS Headache 14.71*** 2.7 (1.3) 2.3 (1.0) 3.8 (.99) 2.0 (1.2) S > LC S > A Sleep disturbance 2.22 3.4 (1.1) 3.1 (1.0) 3.9 (.98) 3.3 (1.1) *** p < .001, ** p < .005, * p <.01 MS = Multiple Sclerosis, LC = Lung Cancer, S = Stress, A = Asthma. For the illness under question, participants rated a sufferer’s average experience of each symptom on a scale from 0 to 5, where 0 = “not at all” and 5 = “would experience these symptoms severely”.

Participants perceived greater presentation of cough and breathlessness in asthma and lung cancer than in MS or stress. They did not differentiate the severity of these symptoms between asthma and lung cancer or between MS and stress. Participants perceived that depression would be less severe in asthma than in any of the other illnesses; they did not differentiate between lung cancer, MS, or stress in the perceived severity of depression. Participants viewed the symptom of decreased mobility as being most pronounced in MS: significantly more severe than in any other illness. They perceived decreased mobility to be more severe in lung cancer than in either asthma or stress, but did not differentiate asthma from stress in terms of mobility. Fatigue was identified as more severe in MS than asthma, but no other differences emerged for this symptom. Pain was identified as more severe in MS and lung cancer relative to asthma, and asthma relative to stress. Participants did not differentiate MS and lung cancer in terms of presence/severity of pain. Visual disturbance was identified as more severe in MS than in lung cancer or asthma; there were no other differences between illnesses for perceived severity of this symptom. Finally, participants perceived that headache presentation would be more severe in stress than in any of the other illnesses; they did not differentiate between lung cancer, MS, or asthma in terms of headache severity. 19 2.3.4.2 Perceived causes Participants were asked to indicate how much they thought each of the factors presented in Table 2 caused the relevant illness. Results showed that there were significant differences between illnesses in how much each of the factors were thought of as causes, for all causes apart from ‘chance or bad luck’ and ‘altered immune system’. Table 2 shows the F ratios, descriptive statistics, and significant differences between illnesses (post-hoc comparisons using Tukey’s HSD).

Table 2 Table to show means (and standard deviation) for causes of illness

Multiple Lung Significant F Sclerosis Cancer Stress Asthma differences MS > LC Hereditary 5.18** 3.8 (.97) 3.0 (.77) 3.0 (.96) 3.6 (.74) MS > S MS > LC Germ or virus 6.37** 3.0 (1.3) 2.1 (1.1) 1.9 (.77) 2.5 (.92) MS > S A > MS Diet 5.67** 1.9 (.91) 2.4 (1.1) 2.9 (.93) 2.6 (1.1) S > MS Chance .25 2.5 (1.3) 2.6 (1.4) 2.8 (1.4) 2.6 (1.2) S > MS Poor medical care in the past 6.81*** 1.8 (.97) 2.5 (1.3) 3.0 (.94) 2.6 (.88) A > MS A > S Pollution 32.87*** 1.9 (.93) 3.9 (.70) 2.7 (1.1) 3.9 (.66) LC > S S > MS A > MS Touching substances at work 8.34*** 1.7 (.83) 2.7 (1.0) 2.4 (1.3) 3.1 (1.2) LC > MS A > S Breathing substances at work 30.74*** 1.7 (.86) 3.9 (.65) 2.7 (1.2) 3.9 (.89) LC > S S > MS S > A Persons behaviour 55.66*** 1.6 (.97) 4.2 (.94) 4.4 (.75) 2.8 (.90) LC > A A > MS S > A Mental attitude 47.76*** 1.9 (1.0) 2.5 (1.1) 4.6 (.58) 2.0 (.92) S > LC S > MS S > A Family problems 52.32*** 1.8 (.89) 2.3 (.97) 4.6 (.57) 2.3 (1.1) S > LC S > MS S > A Overwork 34.46*** 2.2 (1.2) 2.3 (1.2) 4.7 (.49) 2.6 (.96) S > LC S > MS S > A Emotional state 46.64*** 2.0 (.96) 2.5 (.98) 4.5 (.58) 2.1 (.97) S > LC S > MS S > A Ageing 4.33* 2.8 (1.2) 3.3 (.86) 3.4 (.89) 2.5 (1.1) LC > A S > A Alcohol 7.74*** 2.2 (1.1) 2.5 (.81) 3.3 (.95) 2.3 (.86) S > LC S > MS LC > A Smoking 49.46*** 2.0 (1.1) 4.9 (.36) 3.2 (1.1) 4.0 (.71) A > S S > MS S > A Accident or injury 18.28*** 2.1 (1.2) 2.1 (.77) 3.9 (.89) 2.5 (1.1) S > LC S > MS S > LC Personality 40.27*** 1.9 (.95) 3.0 (1.0) 4.4 (.75) 2.1 (.99) LC > A LC > MS Altered immune system .05 3.2 (1.1) 3.2 (.99) 3.1 (1.1) 3.1 (1.1) S > A Lack of control at work 34.02*** 1.7 (.78) 2.3 (.85) 4.0 (.75) 2.3 (1.1) S > LC S > MS

20 S > A Lack of training at work 45.97*** 1.4 (.64) 1.8 (.93) 4.0 (.79) 2.1 (.93) S > LC A > MS S > A S > LC Pressure at work 42.38*** 1.7 (.88) 2.4 (1.0) 4.5 (.58) 2.5 (1.2) A > MS LC > MS S > A Management at work 52.86*** 1.5 (.64) 2.1 (.89) 4.1 (.65) 2.1 (.99) S > LC A > MS S > A Poor support at work 59.61*** 1.5 (.64) 2.1 (.92) 4.4 (.50) 2.4 (1.1) S > LC A > MS *** p < .001, ** p < .005, * p <.01 MS = Multiple Sclerosis, LC = Lung Cancer, S = Stress, A = Asthma. For the illness under question, participants rated the causal strength of each potential cause on a scale from 1 to 5, where 1 = “definitely not a cause” and 5 = “definitely a cause”.

Participants perceived MS to be more attributable to hereditary causes or a germ/virus than lung cancer and stress, but did not distinguish MS from asthma in this regard. They perceived no differences between lung cancer, asthma, and stress in either of these causal influences. Diet and poor medical care in the past were perceived to be stronger influences on asthma and stress than on MS; there were no other significant differences between illnesses for these causes. Pollution and breathing substances at work were perceived as greater influences on asthma and lung cancer relative to stress, and as greater influences on stress relative to MS (no other differences). Touching substances at work was perceived as more contributory to asthma and lung cancer than MS (no other differences). A person’s behaviour was given greater causal weight for stress and lung cancer as compared with asthma, and for asthma as compared with MS (no other differences). There were seven causes that were seen as more influential for stress than any other illness, with no differences between the other illnesses. These causes were: Mental attitude, family problems, overwork, emotional state, alcohol, accident or injury and lack of control at work. Ageing was attributed less causal influence for asthma than for lung cancer and stress (no other differences). Smoking was seen as a greater cause of smoking than asthma, of asthma than stress, and of stress than MS. Personality was attributed more causal influence over stress relative to the other illnesses, and over lung cancer relative to MS and asthma (no other differences). Lack of training at work, management at work, and poor support at work were viewed as having similar causal influences between illnesses. These three causes were seen as more influential for stress as compared with the other illnesses, and for asthma as compared with MS (no other differences). Finally, causal perceptions regarding pressure at work showed a similar pattern of differences: greater influence on stress than on other illnesses and on asthma and lung cancer than on MS (no other differences).

2.3.4.3 Sources of Information Participants were asked to rate the trustworthiness of the sources of illness information presented in Table 3. Results showed that there were significant differences in the perceived trustworthiness of information sources between illnesses: for GPs, the internet, and occupational health professionals. Table 3 shows the F ratios, descriptive statistics, and significant differences between illnesses (post-hoc comparisons using Tukey’s HSD).

21 Table 3 Table to show means (and standard deviation) for trust in sources of information by illness

Multiple Significant F Sclerosis Lung Cancer Stress Asthma differences 7.78*** MS > S GP 6.1 (1.0) 6.0 (.97) 5.2 (.94) 6.5 (1.0) A > S MS > S Internet 4.42* 1.8 (1.5) 4.2 (1.1) 1.7 (1.3) 3.3 (1.3) A > S HSE .20 3.6 (1.4) 3.3 (1.3) 3.4 (1.0) 2.0 (.98) Employer 2.07 4.4 (.80) 3.3 (1.2) 2.0 (1.4) 2.2 (1.1) Friends/family 1.99 3.0 (1.3) 4.4 (.60) 2.3 (1.5) 4.2 (.71) Occupational health 4.60* 4.1 (1.0) 3.8 (.89) 3.4 (1.3) 3.1 (1.2) S > MS professionals Newspapers/magazines .42 4.0 (1.2) 4.0 (.94) 2.0 (1.3) 3.0 (1.1) TV/radio .63 2.9 (1.4) 1.8 (.93) 2.1 (1.2) 1.8 (1.1) *** p < .001, ** p < .005, * p <.01 MS = Multiple Sclerosis, LC = Lung Cancer, S = Stress, A = Asthma. For the illness under question, participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”.

Participants perceived GPs and the internet to be more reliable sources for information on MS and asthma than on stress. No other differences were observed between illnesses for these sources of information. Occupational health professionals were more trusted as sources for stress than for MS. Their perceived trustworthiness did not differ in other comparisons between illnesses.

2.3.4.4 Illness Representations Participants were asked to rate their agreement with 18 illness-related statements from which their illness representations (7 IPQ-R factors and 5 work-related beliefs) could be computed.

IPQ-R illness representations The 7 IPQ-R factor scores were derived from illness questionnaire items (Moss-Morris et al., 2002). These factors and their associated reliabilities (Cronbach’s alpha) and zero- order correlations are presented in Table 4. Two of the factors (Timeline-cyclical and Emotion Representations) were below the recommended reliability for group comparisons (.50; Helmstadter, 1964). However, the majority of factors were of acceptable reliability – despite only having two items per factor. As there are only two items per factor the inter-item correlation is also reported.

Table 4 Reliability and inter-relation of illness representation factors

Correlations Illness Representation 1 2 3 4 5 6 α rii (1) Illness Coherence† (2) Timeline-acute/chronic -.21* .64 .49 (3) Timeline-cyclical .16 -.17 .40 .25 (4) Treatment Control .07 -.23* .22* .66 .49 (5) Personal Control .04 -.30** .01 .18 .75 .62 (6) Emotion Representations -.01 .30** .05 -.29** -.01 .41 .28 (7) Serious Consequences -.14 .40*** -.08 -.32** -.18 .62*** .77 .63 *p<.05, **p<.005, ***p<.001 †This factor was represented by a single item α = Cronbach’s alpha reliability; rii = inter-item correlation

The means and standard deviations for these 7 IPQ-R illness representations by illness type are displayed in Table 5. Results showed that there were significant differences in IPQ-R representations of

22 illness between illnesses for all factors except Timeline-cyclical. Table 5 shows the F ratios and significant differences between illnesses (post-hoc comparisons using Tukey’s HSD).

23 Table 5 Table to show means (and standard deviation) for IPQ-R illness representations by illness

Multiple Lung Significant F Sclerosis Cancer Stress Asthma differences S > MS Illness Coherence 5.28** 2.77 (1.24) 2.86 (1.67) 3.75 (.70) 3.14 (.83) S > LC MS > LC Timeline- MS > A 45.32*** 4.62 (.45) 3.91 (.65) 2.71 (.70) 3.50 (.62) acute/ chronic LC > S A > S Timeline-cyclical 1.82 3.15 (.90) 3.03 (.55) 3.46 (.59) 3.30 (.65) A > LC Treatment Control 5.43** 3.06 (.69) 3.20 (.75) 3.55 (.89) 3.77 (.58) A > MS LC > MS Personal Control 6.94*** 3.54 (.87) 4.42 (.61) 4.24 (.67) 4.17 (.70) S > MS A > MS Emotion MS > A 20.85*** 4.17 (.65) 4.14 (.62) 3.87 (.55) 3.09 (.50) LC > A Representation S > A Serious MS > S 35.36*** 4.59 (.56) 4.57 (.55) 4.12 (.50) 3.15 (.73) LC > A Consequences S >A *** p < .001, ** p < .005, * p <.01 MS = Multiple Sclerosis, LC = Lung Cancer, S = Stress, A = Asthma. For the illness under question, scores for each illness representation reflect agreement with this view of illness on a scale from 1 to 5, where 1 = “strongly disagree” and 5 = “strongly agree”.

Participants perceived stress to be more understandable (higher illness coherence) than both MS and lung cancer. No other differences in coherence were observed between illnesses. They perceived MS to be a more chronic condition than any of the other illnesses, and stress to be more acute than any other illness, but did not differentiate asthma and lung cancer in terms of duration. Asthma was represented as more treatable than lung cancer and MS (no other differences observed). MS was perceived as less amenable to personal control than any other illness (no other differences). Asthma was perceived as having less pronounced negative emotional effects as compared with any of the other illnesses (no other differences). Asthma was also seen as having less serious consequences than other illnesses. Stress was viewed as less serious than MS, but was not differentiated from lung cancer. Consequences of lung cancer were not distinguished from consequences of MS.

Work-related Illness Representations In addition to IPQ-R factors, 5 (single-item) scores reflecting beliefs about illness in relation to occupation were examined as illness representations (see Table 6). Results showed that there were significant differences in work-related representations of illness between illnesses for all belief-statements except one: “Person should be prevented from doing certain jobs”. Table 6 shows the F ratios and significant differences between illnesses (post-hoc comparisons using Tukey’s HSD).

24 Table 6 Table to show means (and standard deviation) for occupation-related illness representations by illness. Multiple Lung Significant F Sclerosis Cancer Stress Asthma differences Person would MS > S MS > A have to stop work 16.66*** 2.58 (1.10) 2.50 (.86) 1.61 (.63) 1.31 (.54) LC > S permanently LC > A Would cause a MS > S MS > A person to take 15.39*** 4.15 (.60) 4.18 (.50) 3.11 (.99) 3.04 (1.00) LC > S days off LC > A Person should tell MS > LC 6.32** 4.22 (.70) 3.45 (1.10) 3.18 (1.02) 3.48 (.87) MS > S their employer MS > A Employer should protect people at work from 4.57* 4.11 (.93) 4.36 (.79) 3.54 (.88) 4.00 (.66) LC > S anything worsening symptoms Person should be prevented from 1.83 3.19 (1.11) 2.82 (1.26) 2.61 (1.10) 2.48 (1.30) doing certain jobs *** p < .001, ** p < .005, * p <.01 MS = Multiple Sclerosis, LC = Lung Cancer, S = Stress, A = Asthma. For the illness under question, scores for each occupational illness representation reflect agreement with this view of illness on a scale from 1 to 5, where 1 = “strongly disagree” and 5 = “strongly agree”.

A similar pattern of differences between illnesses was found for representations of illness as a cause of medical retirement (“Person would have to stop work permanently”) and of illness as a cause of absenteeism (“Would cause a person to take days off”). Both representations were stronger for MS and lung cancer as compared with stress and asthma. MS was not differentiated from lung cancer and stress was not differentiated from asthma in relation to illness-precipitated retirement/absenteeism. Belief that a person with illness should inform their employer was stronger with regard to sufferers of MS than with regard to sufferers of any of the other illnesses under question (no other differences were observed). Finally, participants had a stronger representation of the employer’s duty to protect sufferers from occupational illness-aggravation for lung cancer than for stress (no other differences).

2.3.4.5 Illness Knowledge Participants were asked to provide answers to questions assessing illness-related knowledge and to rate their confidence that the answer they provided is correct. A knowledge calibration score was also calculated by comparing the degree of actual accuracy (percentage correct on knowledge questions) with the perceived level of accuracy (confidence). A positive coefficient indicates overconfidence (participants think they know more than they actually do), a negative score indicates under-confidence (participants know more than they actually think they do) and zero indicates perfect calibration (participants know what they think they know).

The means and standard deviations for knowledge, knowledge confidence, and knowledge calibration by illness type are displayed in Table 7. Results showed that there were significant differences in all these measures. Table 7 shows the F ratios and significant differences between illnesses (post-hoc comparisons using Tukey’s HSD).

25 Table 7 Table to show means (and standard deviation) for illness-related knowledge, confidence in knowledge, and knowledge calibration

Multiple Lung Significant F Sclerosis Cancer Stress Asthma differences MS > LC Knowledge 85.19 59.72 84.09 62.50 MS > A 11.59*** (% correct) (14.31) (25.92) (14.53) (20.85) S > LC S > A Confidence in 83.95 62.50 63.26 56.94 MS > LC knowledge 14.17*** MS > S (14.79) (20.26) (13.03) (16.05) (% certainty) MS > A Knowledge -3.70 -62.50 -16.67 MS > S calibration 4.07** 8.33 (83.58) (56.63) (70.61) (75.78) LC > S (0 = calibrated) ***p<.001, **p<.01 MS = Multiple Sclerosis, LC = Lung Cancer, S = Stress, A = Asthma.

Participants were more accurate in their answers to MS and stress related questions, as compared with answers to lung cancer and asthma related questions. There were no differences in accuracy between MS and stress or between lung cancer and asthma (questions for lung cancer and asthma were the same). Participants were more confident about their answers to MS-related questions than their answers to other illness-related questions. There were no differences between lung cancer, stress, and asthma despite the relatively superior accuracy of participants for stress-related questions. In terms of knowledge calibration, participants were more under-confident about their stress-related knowledge as compared with their MS and lung cancer knowledge. No other differences in calibration emerged between illnesses.

2.3.5 Discussion The results from this pilot study show that the main items to measure illness representations, symptoms, trust and knowledge showed no floor or ceiling effects. Importantly, most of the illness representation scales in this small sample were reliable enough for group comparisons: providing an encouraging indication that these scales would be acceptable for comparing larger expert and lay samples in Main Study 2. The measure of work-related causes distinguished between the type of illness studied, as did the symptoms, sources of information, and illness representation factors. As such, these data provide evidence that the structure and nature of the instrument to be used in the main field based experiment is reliable and able to discriminate in meaningful ways between the illnesses to be studied.

2.4 MAIN STUDY 2: NATIONAL RANDOMISED FIELD-BASED EXPERIMENT AND TARGETING OF EXPERTS

2.4.1 Aim of Study A randomised field-based experiment was conducted to explore the illness perceptions of a large scale random sample of lay people and a sample of experts, for four illnesses: Multiple Sclerosis, lung cancer, asthma and stress. The study aimed to discover whether these two groups characterise occupational and non-occupational illnesses in the same way, in terms of causes, symptoms, control/cure and timeline. It also explored the main sources trusted by these two groups to provide information about those illnesses. In addition specific objective knowledge of factors pertinent to each illness was tested. The study explored whether lay people and experts have similar models of occupational and non-occupational illnesses.

26 2.4.2 Methods 1: National Randomised Field Experiment (Lay Respondents)

2.4.2.1 Design (Lay Respondents) The 4 versions of the questionnaire were randomly allocated to 12,000 randomly selected members of the UK population. This results in a 1-way between subjects experimental field study.

2.4.2.2 Disease manipulation/materials One of the four versions (i.e., illnesses) of the questionnaires developed from Pilot Study 2 was sent to each potential participant. See appendix 4 for finalised versions of questionnaires.

2.4.2.3 Sampling 12,000 questionnaires were sent out to random sample of the UK population (over 18 years of age) in the following conditions: 3,000 lung cancer, 3,000 Multiple Sclerosis, 3,000 stress and 3,000 asthma. Names and addresses of survey recipients were obtained via a direct mailing company. 12,000 individual names were sampled from the electoral roll. To retain participant anonymity, members of the research team had no access to participant details i.e. names and addresses. The following sampling procedure was used, in order to reflect the demographic spread of the UK population:

For each of the four illnesses, questionnaires were sent out to the following samples: • England - 1,050 male names and addresses, 1,050 female names and addresses. • Scotland - 150 male names and addresses, 150 female names and addresses. • Northern Ireland - 150 male names and addresses, 150 female names and addresses. • Wales - 150 male names and addresses, 150 female names and addresses.

All data was screened at individual level against Deceased files, Gone-away files and MPS (Marketing Preference Service) records. All output was supplied with an age profile spectrum that is average for the UK, based on the median age being 51. All letters were addressed to the individual rather than ‘the occupier’ in order to maximise participation. Envelopes were also addressed to the individual to maximise opening of the survey. Freepost reply envelopes were included in each questionnaire pack.

2.4.2.4 Participants 1947 respondents were obtained from the random-sampling. Of these, 53 respondents were excluded from the ‘lay’ population sample due to their occupation: these respondents indicated that they were working in a role requiring a higher qualification and vocational experience relating to occupational disease (e.g., medical doctors and nurses), and were added to the ‘expert’ sample (discussed later). The remaining 1894 respondents to the random-sample mail-survey were defined as ‘lay’ participants on the basis of their occupation (not indicative of expertise in disease). Lay respondents had a mean age of 41.7 years (min. 17 years, max. 77 years). Each respondent completed one version of the questionnaire (Multiple Sclerosis n=426; lung cancer n=552; stress n=476; asthma n=440). Of those who indicated their sex, 64.1% were female. 93.6% of all participants had never suffered from a work-related illness. Only 5% had suffered from an occupational illness. The remaining participants did not respond to this item. 37% of all participants, however, knew someone who had suffered from a work-related illness.

Lay participants were asked whether they had suffered from or knew anyone who had suffered from the illness relevant to their questionnaire. 3.5% of MS-questionnaire respondents had suffered from MS and 58.9% knew someone with MS. Of respondents to the lung cancer questionnaire, 0.4% had suffered from lung cancer and 52.7% knew someone who had suffered from lung cancer. 72.5% of stress-questionnaire participants reported that they had suffered from stress. Of these, 29.1% said that they had taken time off because of it. 88.4% of participants knew someone who had suffered from stress. Finally, 25.7% of respondents suffered from asthma, with 91.1% knowing someone who 27 suffered from asthma. Thus stress and asthma have the highest reported frequencies (for both personal suffering and known sufferers).

2.4.2.5 Response rate Three hundred and five surveys were ‘returned to sender’ due to the named individual no longer residing at the property. 1947 completed surveys were received. This represents a response rate of 16.6%. The survey response rate was comparable to rates in other research of this kind. For example, Larson and Chow (2003), in an experimental study of mail survey response-inducement, obtained a response rate of 14% using personalised cover letters but no monetary incentives (methods used in the present survey).

2.4.2.6 Ethics: Cover letter and information sheet Cover letters and information sheets were specific to the illness covered in the survey. The information sheets listed general and illness specific, relevant helpline numbers and contact details for members of the project team. Information sheets were included with the survey in case reading about an illness causes the recipient to worry. Permission was obtained to include the helpline numbers and web site addresses of relevant charities. Permissions to use charity helpline numbers was obtained from The British Lung Foundation, The National Asthma Campaign, the Multiple Sclerosis Society and the Health and Safety Executive. A braille and large print version of the survey were made available on request. A paragraph included in the covering letter emphasised that the study was voluntary and that all responses were anonymous.

2.4.2.7 Data checks: Reliability and input errors Ten percent of the data were randomly selected and data entry checked against the original questionnaires. There were 11 recording errors out of 16,800 data-points (200 surveys) checked, which gives an overall reliability of 99.94%. All data was checked for out of range scores: 2 were uncovered (representing an error rate of 0.00001%). All identified errors were corrected.

2.4.3 Methods 2: Targeted Survey (Expert Respondents)

2.4.3.1 Design (Expert Respondents) The 4 versions of the questionnaire were randomly allocated across 4 targeted expert groups. The targeted ‘experts’ all had higher qualifications relating to occupational health. This results in a 1-way between subjects experimental field study.

2.4.3.2 Disease manipulation/materials One of the four versions (i.e. illnesses) of the questionnaires (developed from Pilot Study 1) was sent/administered to each potential participant.

2.4.3.3 Sampling The 4 targeted samples were as follows: (1) 39 health professionals from 2 HSE conferences, (2) 29 chartered health psychologists at the BPS Division of Health Psychology conference, (3) 300 chartered occupational/health psychologists via a mail-out to names randomly selected from the BPS web- directory of health and occupational specialist psychologists, and (4) 8 members of the Association of Local Authority Medical Advisors. The latter target group were approached through an advertisement placed on their web-site: surveys were sent to individual members on request.

28 For the mail-survey of chartered psychologists, all letters were addressed to the individual rather than ‘the occupier’ in order to maximise participation. Envelopes were also addressed to the individual to maximise opening of the survey. Freepost reply envelopes were included in each questionnaire pack.

2.4.3.4 Response rate (for sample 3: survey of chartered psychologists) Two surveys were ‘returned to sender’ due to the named individual no longer residing at the targeted address. One hundred and eleven completed surveys were received. This represents a relatively high response rate of 37.2%, given the low level of response inducement (Larson and Chow, 2003).

2.4.3.5 Participants In all, 240 ‘expert’ participants were obtained. Further to the 4 target samples, this total included 53 respondents from the randomised national survey: these respondents indicated that they were working in a role requiring a higher qualification and vocational experience relating to occupational disease (e.g., medical doctors and nurses). Expert participants had a mean age of 45.8 years (min. 23 years, max. 78 years). Each respondent completed one version of the questionnaire (Multiple Sclerosis n=45; lung cancer n=60; stress n=77; asthma n=58). Of those who indicated their sex, 70% were female. 91.3% of all participants had never suffered from a work-related illness. Only 7.9% had suffered from an occupational illness. The remaining participants did not respond to this item. 61.7% of all participants, however, knew someone who had suffered from a work-related illness.

Expert participants were asked whether they had suffered from or knew anyone who had suffered from the illness relevant to their questionnaire. 2.2% of MS-questionnaire respondents had suffered from MS and 84.4% knew someone with MS. Of respondents to the lung cancer questionnaire, none had suffered from lung cancer personally, but 60% knew someone who had suffered from lung cancer. 72.7% of stress-questionnaire participants reported that they had suffered from stress. Of these, 26.3% said that they had taken time off because of it. 88.3% of participants knew someone who had suffered from stress. Finally, 13.8% of asthma respondents suffered from asthma, with 86.2% knowing someone who suffered from asthma. Thus stress and asthma have the highest reported frequencies (for both personal suffering and known sufferers). The percentage of expert MS respondents who knew sufferers of MS was notably higher than the parallel percentage for lay MS respondents (84.4% versus 59.8%).

2.4.3.6 Ethics: Cover letter and information sheet These were as for the randomised national field survey (discussed previously).1

1 Data checks were not carried out for the experiment sample due to its smaller size 29 2.5 MAIN STUDY 3: EXPLORATION OF LAY AND EXPERT ‘COGNITIVE MAPS’

2.5.1 Aim of Study

The study used structural cognitive mapping techniques with a sample of lay and experts, to explore perceived causal links between potential risk factors for the four illnesses examined in the National Field based experiment (Main Study 2): asthma, lung cancer, stress and multiple sclerosis.

2.5.2 Methods

2.5.2.1 Participants 30 participants completed the cognitive mapping exercise; they produced separate maps for each of the 4 illnesses examined. Participants were classified by occupation as ‘lay’ or ‘expert’. ‘Expert’ participants were defined as those possessing a higher qualification and vocational experience relating to occupational disease: in the present sample, ‘expert’ participants included respiratory nurses, MS specialist nurses, a GP, and a psychiatrist. ‘Lay’ participants constituted 50% of the total sample, and these individuals had a broad range of occupations - including a baker, a systems engineer, and an administrative clerk. 53.3% of lay participants and 80% of expert participants were female.

Participants were asked whether they had suffered from or knew anyone who had suffered from the illnesses to be mapped. Of the lay participants, 20% had suffered from stress and 13.3% had suffered from asthma. None of the lay participants had personally suffered from either MS or lung cancer. 42.9% of lay participants knew someone who had suffered from stress; 21.4% knew someone with MS; 21.4% knew someone with lung cancer; and 64.3% knew someone with asthma. Of the experts, 13.3% had suffered from stress and 13.3% had suffered from asthma. None had personally suffered from MS or lung cancer. All expert participants knew someone who had suffered from stress; 86.7% knew someone with asthma, 66.7% knew someone with MS; and 80% knew someone with lung cancer.

2.5.2.2 Materials Nine risk factors were identified, to be explored, for each illness. Five of these factors were identified from the interview study (Main Study 1) as the most commonly mentioned causes. Frequencies for the factors identified in Main Study 1 are presented in Table 8. Additional causes were identified through web based medical resources where not enough risk factors were identified through the interviews alone (it is desirable to analyse networks involving at least 7 risk factors; for present purposes it was pre-decided that 9 risk factors would be obtained for each illness). This was entirely the case for asthma, which did not feature in the interviews. Attempts were made to match the causes across the illness. For example, external factors were match in terms of carcinogens, job-characteristics, climate, irritants, workload, and air pollution (in both asthma and lung cancer). This was not a perfect matching, but served to allow where possible comparisons between the risk factors across the illnesses.

30 Table 8 The 9 risk factors for each of the four illnesses (for risk factors identified from Main Study 1, frequency counts are shown in parentheses)

Multiple Lung Cancer Stress Sclerosis Asthma 1 Carcinogens Job Climate (5) Irritants External Factors (frequency=25) dissatisfaction (9) 2 Diet/exercise Diet/exercise Diet/exercise Diet/exercise Health Behaviour 3 Air pollution Workload(30) Stress (3) Air pollution External factors (28) 4 Medical history Domestic Medical history Medical history Previous History (4) situation (24) (6) 5 Smoking (37) Social Virus (9) Allergies Triggers support/coping mechanisms (20) 6 Genetics (8) Personality (9) Genetics (15) Genetics Internal factors – pre-dispositions 7, 8, 9 Demographics Demographics Demographics Demographics Demographics (age, sex, ethnic (age, sex, ethnic (age, sex, ethnic (age, sex, ethnic background) background) background) background)

2.5.2.3 Procedure Participants were asked to indicate by use of arrows on a diagram to what extent each of nine risk factors influenced (either positively or negatively) each particular illness. An example set of instructions for asthma is given below. See appendix for copy of instructions for participants for all 4 illnesses.

Example instruction for asthma: The following factors may be important in causing asthma: genetics, irritants, diet/exercise, air pollution, past medical history, allergies, age, sex, ethnic background. We would like you to make up a diagram using the labels provided, of how you think these causes are linked to lung cancer and to each other, using arrows to indicate the direction of the effect. We would also like you to rate the strength of the link on a scale of 1-100 and write the appropriate number onto the diagram. If you think that the factor has a negative effect (i.e. causes the illness or makes it worse) then place a minus sign (-) after the number. If you think that the factor has a positive or beneficial effect (i.e. can make the illness better or alleviate symptoms), then place a plus sign (+) after the number. If you do not think that a cause has an important effect leave it off your diagram. Only include those causes that you think are important.

31 3 CLASSIFYING ILLNESSES AS OCCUPATIONAL OR NON OCCUPATIONAL

This chapter focuses on the main question outlined below:

What do people (experts and the lay public) class as occupational diseases?

The following main sources of data (described in Chapter 2) will be used to address this question:

• Interviews with lay and expert people (Pilot Study 1 & Main Study 1)

3.1 RESULTS FROM PILOT STUDY 1: IDENTIFYING OCCUPATIONAL AND NON OCCUPATIONAL DISEASES

Results were collated and analysed using SPSS version 10.

3.1.1 Statistical analysis Clusters of diseases were identified using a hierarchical cluster analysis. Ward’s method was employed and proximities were based on squared Euclidean distance. A three cluster solution was chosen as the most coherent and interpretable.

Diseases were perceived to be non-occupational in origin, highly occupational in origin and ambiguous. Mean scores are shown in Table 9 below – a score of 10 indicates that illness are work related and 1 definitely not work related.

Table 9 Perceptions of diseases as occupational in origin

Cluster Non Occupational Highly Occupational Ambiguous Mean 2.1 7.0 4.4

Results for the 3 cluster solution are illustrated in Table 10 (individual means are presented for each disease).

32 Table 10 Identified disease clusters

Non- Occupational M Highly Occupational M Ambiguous M Lung Cancer 3.15 Hand/Arm Vibration 7.12 Asthma 4.37 Syndrome Tuberculosis 2.24 Carpal Tunnel Syndrome 6.04 Tetanus 3.38

Shingles 2.57 Asbestosis 7.63 Chronic Fatigue 4.82

Bone Cancer 1.83 Stress 7.63 Bronchitis 4.31

Stomach Cancer 2.19 Back Pain 6.85 Hernia 5.38

Measles 1.54 Coronary Heart Disease 4.10

Multiple Sclerosis .98 Dermatitis 4.78

Leukaemia 1.65

Thus diseases such as lung cancer and multiple sclerosis are not seen as work related, stress is seen as work related, and asthma is seen as ambiguous.

Diseases were identified from each cluster based on their individual means. From each category, illnesses with the highest, lowest, and middle rankings were chosen. As stress and asbestosis had identical means, it was decided to include both. The following diseases were selected for interviews conducted in Main Study 1:

Non-occupational: multiple sclerosis, lung cancer, tuberculosis. Highly-occupational: carpal tunnel syndrome, stress, asbestosis, back pain. Ambiguous: tetanus, hernia, dermatitis.

3.1.2 Conclusions Based on these initial pilot data it is clear that people can distinguish between illnesses that they perceive as occupational and those that are definitely not. However, and interestingly, there are certain illnesses where this clear distinction is much less certain.

3.2 RESULTS FROM MAIN STUDY 1: LAY AND EXPERT INTERVIEWS

3.2.1 Results As asbestosis and stress had the same means, asbestosis was originally included as this is classed as disease rather than a ‘mental state’ (e.g., stress). However, it was decided after 3 interviews to substitute stress for asbestosis as it transpired that asbestosis was already being discussed by participants as part of the lung cancer section. In addition, discussion with experts revealed stress to be one of the main causes of patient referral in participants’ clinics, and it was therefore thought to be more pertinent

33 3.2.1.1 Data Analysis Data from the interviews were transcribed into Microsoft WordTM files. These files were then formatted in order to import them into the data analysis programme. The qualitative data analysis software package QSR NUDIST was used to organise and analyse the data. NUDIST supports the process of coding data into an index system, allowing future searches of text and patterns of coding.

Transcribed data was coded into the categories and sub-categories based on Leventhal et al’s (1998) illness representation categories, i.e. symptoms, causes, control, timeline.

Quantitative data was collated and analysed using SPSS version 10.

3.2.1.2 Qualitative data A coding framework based originally on Leventhal et al.’s (1998) illness representations model was developed, using themes emerging from the interview data. Themes were: o Treatments – alternative therapies, exercise, surgery, rest, drugs, lifestyle o Symptoms – physical, behavioural, psychological o Causes – environmental, lifestyle (work/habits), biological (genetics/infection), personality o Timeline – development (quick, gradual, varies by type or by person), presence of symptoms (always present/fluctuates). The full coding framework of categories obtained through the interviews can be seen in Figure 3.

34 TREATMENTS

ALTERNATIVE EXERCISE SURGERY REST DRUGS LIFESTYLE THERAPIES

TIMELINE SYMPTOMS

DEVELOPMENT PRESENCE OF SYMPTOMS

PHYSICAL BEHAVIOURAL PSYCHOLOGICAL QUICK GRADUAL VARIES ALWAYS FLUCTUATE PRESENT

BY TYPE BY CAUSES PERSON

ENVIRONMENTAL LIFESTYLE BIOLOGICAL PERSONALITY

WORK HABITS GENETICS INFECTION

Figure 3 Nudist framework of interview-derived illness categories 35 3.2.1.3 Quantitative data Lay people were significantly more willing to estimate the number of new cases of the diseases than the experts for all six diseases (see Table 11 below). For tetanus, hernia, and lung cancer, experts were also significantly less willing to estimate the percentage of cases caused by work (see Table 12). Of those that offered estimates, there were no differences between lay people and experts in their estimates of the number of new cases of each disease. However, their estimates of the percentage of those cases caused by work did differ for some diseases. For carpal tunnel syndrome, stress, and hernia, lay people attributed a higher percentage of cases to be caused by work than experts. These particular illnesses have multiple, interactive causes, which experts were able to outline in the interviews. For example, hernia is typically associated by lay people with lifting heavy objects. However, an anatomical weakness (either congenital or as a result of ageing) is usually present in order for lifting heavy objects to cause a tear in the muscle wall. Similarly, carpal tunnel syndrome was identified by experts as being at present a ‘popular’ occupational condition, associated by the lay people in this study with repetitive action. However, most frequently carpal tunnel syndrome is caused by factors such as pregnancy, obesity or other underlying physiological or anatomical dispositions.

Descriptive summaries for these estimates for lay people and experts can be seen in the tables below.

Table 11 Table to show estimates of number of new cases per year for lay people and experts

Estimated Number of New Cases by Disease Multiple Sclerosis Carpal Tunnel Syndrome Tetanus Expert Lay Expert Lay Expert Lay % giving 33 84 29 79 33 68 estimate F 13.64** 12.92** 5.32* Mean 104429 31025 138667 57177 80724 70582 F 2.36 .68 .02 Median 50000 5000 4000 5000 50 2000 Mode 5000 50000 2000 5000 5 2000

Lung Cancer Stress Hernia Expert Lay Expert Lay Expert Lay % giving 43 100 38 74 33 95 estimate F 24.07*** 5.56* 25.46*** Mean 81667 374455 1825000 486955 46667 117224 F .57 2.02 .48 Median 60000 40000 500000 15000 40000 11500 Mode 100000 100000 200000 10000 10000 5000 *** p<.001, ** p<.005, * p<.05

36 Table 12 Table to show estimates of percentage of new cases caused by work for lay people and experts

Estimated Percentage of Cases Caused by Work Multiple Sclerosis Carpal Tunnel Syndrome Tetanus Expert Lay Expert Lay Expert Lay % giving 86 68 71 84 38 95 estimate F 1.70 .91 20.61*** Mean 0 8 26 73 21 38 F 2.39 23.31*** 3.00 Median 0 0 10 77 7 50 Mode 0 0 10 90 0 50

Lung Cancer Stress Hernia Expert Lay Expert Lay Expert Lay % giving 81 100 86 79 52 100 estimate F 4.25* .30 16.41*** Mean 10 21 53 68 28 46 F 3.62 4.66* 5.27* Median 10 20 60 70 27 50 Mode 10 20 50 50 20 50 *** p<.001, ** p<.005, * p<.05

3.2.2 Discussion These results indicate that lay people are more willing to estimate a number of people who get these illnesses and how many get it as a function of work. This is not the same as saying that the lay sample see work as a cause. Rather, when asked to estimate cases – as the question indicates that work may be a causal factor – then lay people are more willing to do this than expert participants. Thus, the lay sample appear more open to the suggestion that work causes – or is at least is responsible for more new cases – illness than experts. This implies that expert knowledge may act as one factor that reduces their openness to the idea of a single cause. It also implies that lay people are more suggestible about work as a cause of illness and less likely to question it.

37 4 PERCEPTIONS OF ILLNESS CAUSATION

This chapter addresses the following question about the perceived causes of illness, including - for the first time in an illness representation study - work characteristics.

• How do expert and lay groups differ in terms of their perceptions of work and non-work factors as causing MS, asthma, Lung cancer and stress?

4.1 COMPARING LAY AND EXPERT PERCEIVED CAUSES OF ILLNESS (ACROSS ALL 4 ILLNESSES)

All comparative analyses of lay and expert groups draw on survey data from the national randomised field study and targeted sampling of experts (Main Study 2), except for the comparison of cognitive maps (discussed later in this chapter). Initial analyses looked at general differences (across all 4 illnesses) in causal attributions between lay and expert groups2. Figure 4 shows the means for causes that were given significantly different weighting by expert versus lay participants.

MANOVA showed that experts tended to make stronger causal attributions overall [F (1, 1788) = 10.35, p=.001] and univariate analyses showed that they gave significantly more weight to the following causes (relative to lay people): a person’s behaviour [F (1, 2074) = 47.39, p<.001], a person’s mental attitude [F (1, 2091) = 8.41, p=.004], a person’s personality [F (1, 2067) = 32.50, p<.001], altered immunity [F (1, 2045) = 18.30, p<.001], overwork [F (1, 2083) = 4.68, p=.031], lack of control at work [F (1, 2084) = 38.51, p<.001], lack of training at work [F (1, 2086) = 16.94, p<.001], pressure at work [F (1, 2092) = 6.86, p=.010], management at work [F (1, 2085) = 13.86, p<.001], and poor support at work [F (1, 2092) = 13.37, p<.001].

In terms of work characteristics, experts, relative to lay people, perceive these as a significantly more important cause of illness in general. This should be seen in light of the results from Chapter 3 which indicated that lay samples may be more susceptible to the idea that work causes illness. The implication is that if experts perceive work characteristics as a more important cause of illness and lay people are open to suggestion, then the experts may make this suggestion more salient for lay people.

2 General note: Much of the data collected was non-normally distributed. However, all reported parametric analyses throughout this report were replicated using non-parametric analyses. 38 5

4 Lay 3 Expert Rating 2

1

r rk rk k rk rk rk u de lity ity o vio a wo w ttitu on mun at wo ha s l at wo t at wo e er im Over o e r tal a p ur n ed ntr s po n's b e 's r p o m res su rs s on Alte of co r e ' s P on er A p s p ack ManagementPoo at er A L Lack of training at wor p A Average attribution strength Cause

Participants rated the causal strength of each potential cause on a scale from 1 to 5, where 1 = “definitely not a cause” and 5 = “definitely a cause”. Error bars in figures represent standard errors of the means. Figure 4 Significant group differences in perceived causes of illness (lay versus expert)

4.2 COMPARING LAY AND EXPERT PERCEIVED CAUSES OF ILLNESS (BY ILLNESS)

The previous analyses did not differentiate between the four illnesses. Therefore, these analyses looked at differences between lay and expert groups in their causal attributions for each illness (examined separately). For each illness, a series of one-way ANOVAs were conducted with potential causes as dependent variables and expertise group as the independent variable. Scores for each cause reflect their perceived contribution to illness (higher scores indicate greater causal influence).

4.2.1 Perceived causes of MS Figure 5 shows significant mean differences between groups (lay versus expert) with regard to perceived causes of MS. Lay participants perceived heredity [F (1, 461) = 4.63, p=.032] and accident/injury [F (1, 454) = 4.50, p=.034] as more contributory to MS (relative to experts). Experts gave relatively greater causal weight to altered immunity [F (1, 450) = 5.99, p=.015]. No other significant differences were found between lay and expert causal attributions.

39 Perceived causes of MS

5

4

Lay 3 Expert

Attribution strength strength Attribution 2

1 Heredi tary Acci dent or injury Altered Immunity Cause

Participants rated the causal strength of each potential cause on a scale from 1 to 5, where 1 = “definitely not a cause” and 5 = “definitely a cause”. Figure 5 Significant group differences in perceived causes of MS (lay versus expert)

4.2.2 Perceived causes of lung cancer Figure 6 shows significant mean differences between groups (lay versus expert) with regard to perceived causes of lung cancer. Lay participants perceived poor medical care in the past [F (1, 584) = 4.29, p=.039] as more contributory to lung cancer (relative to experts). Compared with lay people, experts gave greater causal weight to chance/bad luck [F (1, 586) = 6.44, p=.011], a person’s behaviour [F (1, 594) = 98.12, p<.001], a person’s mental attitude [F (1, 598) = 5.61, p=.018], a person’s personality [F (1, 593) = 39.85, p<.001], altered immunity [F (1, 595) = 21.21, p<.001], and lack of control at work [F (1, 602) = 20.89, p<.001]. No other significant differences were found between lay and expert causal attributions.

40 Perceived causes of Lung Cancer

5

4 Lay 3 Expert 2 Attribution strength strength Attribution 1

st ity rk al on at wo rs r bad luck n the pa ehaviour ol o b e i 's 's pe car contr ance l son f h a r son o C pe er k A p ac A ltered immune systemL medic A A person's mental attitude Poor Cause

Participants rated the causal strength of each potential cause on a scale from 1 to 5, where 1 = “definitely not a cause” and 5 = “definitely a cause”. Figure 6 Significant group differences in perceived causes of lung cancer (lay versus expert)

4.2.3 Perceived causes of stress Figure 7 shows significant mean differences between groups (lay versus expert) with regard to perceived causes of stress. Lay participants perceived diet [F (1, 536) = 7.13, p=.008] as more contributory to stress (relative to experts). Compared with lay people, experts gave greater causal weight to a person’s personality [F (1, 538) = 11.43, p=.001], lack of control at work [F (1, 537) = 27.65, p<.001], lack of training at work [F (1, 538) = 14.14, p<.001], management at work [F (1, 539) = 12.03, p=.001], and poor support at work [F (1, 545) = 8.22, p=.004]. No other significant differences were found between lay and expert causal attributions.

41 Perceived causes of Stress

5 4 Lay 3 Expert 2 1 Attribution strength strength Attribution ts ty rk rk k i o or ali w w son at g hab t rt at n er rol at work p t en po eati gm or t na r sup ie of training at wo D Ma A persons ack of con Poo L Lack Cause

Participants rated the causal strength of each potential cause on a scale from 1 to 5, where 1 = “definitely not a cause” and 5 = “definitely a cause”. Figure 7 Significant group differences in perceived causes of stress (lay versus expert)

4.2.4 Perceived causes of asthma Figure 8 shows significant mean differences between groups (lay versus expert) with regard to perceived causes of asthma. Compared with lay people, experts gave greater causal weight to a person’s behaviour [F (1, 486) = 7.34, p=.007] and altered immunity [F (1, 479) = 6.55, p=.011]. No other significant differences were found between lay and expert causal attributions.

Perceived causes of Asthma

5

4

Lay 3 Expert

2 Attribution strength strength Attribution 1 A person's behaviour Altered immuni ty Cause

Participants rated the causal strength of each potential cause on a scale from 1 to 5, where 1 = “definitely not a cause” and 5 = “definitely a cause”. Figure 8 Significant group differences in perceived causes of asthma (lay versus expert)

42 4.3 INTERIM CONCLUSIONS

There are two main findings from the above analysis. First experts, compared to lay participants, were more likely across the 4 illnesses to rate most causes as more important. Second, and related, experts were more likely to see stress – traditionally viewed as an occupational illness – as caused by work- characteristics. It should be noted that stress – as all of the other illnesses – was not defined in any way for the participants. Similarly, experts were also more likely to see work characteristics as cause of lung cancer (which might be in some cases an occupational illness). There were no differences between expert and lay participants with respect to work characteristics for MS and asthma.

4.4 LAY AND EXPERT MODELS OF ILLNESS CAUSATION

These comparisons drew on Main Study 3 (structural cognitive map data). For each illness, separate expert and lay cognitive maps were produced. Within each group, composites were obtained by examining paths between any two factors for each of the 15 participants. Identified significant pathways reflect perceived causal strength (magnitude of influence attributed to a link).

The following sub-sections present and discuss cognitive maps for each illness. In each figure, lay and expert models are shown side-by-side for comparison. Arrow widths are indicative of the perceived mean strength of each connection (from 1 to 100). The following key is used in all figures:

Low strength link (10-39) Medium strength link (40-69) High strength link (70-100)

4.4.1 MS Cognitive maps for MS are shown in figure 9.

Figure 9 Lay (left) and expert (right) maps of perceived causal paths of MS

The cognitive map produced by lay participants posits direct paths between causes and the target illness (MS), with no paths between different causes. The most frequently identified cause of MS was genetics (endorsed by 10 participants). All identified connections were in the low range of strength (10-39)

43 except for genetics (mean strength of 52.7). Three potential causes were not identified by lay participants as being linked to the target illness or to other causes: climate, sex, and ethnic background.

In contrast to the map produced by lay participants, the expert model specifies links from all potential causes to MS: including causal links from climate, sex, and ethnic background. The most frequently identified causes of MS were genetics, a virus, diet/exercise, and age (all endorsed by 10 participants); this differed from the lay model, wherein the influence of genetics was singularly most popular. Experts also posited a link from MS back to diet/exercise (indicating that having the illness would influence a person’s lifestyle) that was not present in the lay model. All identified causes of MS were in the low range of strength (10-39).

4.4.2 Lung cancer Cognitive maps for lung cancer are shown in figure 10.

Figure 10 Lay (left) and expert (right) maps of perceived causal paths of lung cancer

The cognitive map produced by lay participants posits direct paths between causes and the target illness (lung cancer), with no paths between different causes. The most frequently identified cause of lung cancer was smoking (endorsed by all participants). Smoking was also attributed the greatest strength of all causes (mean strength of 90.4). Carcinogens, genetics and air pollution were in the medium range of strength (40-69). Age, medical history, and diet/exercise were in the low range of strength (10-39). Two potential causes were not identified by lay participants as being linked to the target illness or to other causes: sex and ethnic background.

In contrast to the map produced by lay participants, the expert model specifies links from all potential causes to lung cancer: including causal links from sex and ethnic background. The expert model also posits an indirect pathway to lung cancer through a link from air pollution to carcinogen exposure. The most frequently identified causes of lung cancer were smoking and carcinogens (both endorsed by all participants); this differed from the lay model, wherein the influence of smoking was singularly most popular. In the expert model, both smoking and carcinogens were in the high range of causal strength (70-100). Genetics and age were in the medium range of strength (40-69), and all other connections (including the air pollution-carcinogens link) were in the low range (10-39).

4.4.3 Stress Cognitive maps for stress are shown in figure 11.

44 Figure 11 Lay (left) and expert (right) maps of perceived causal paths of stress

The cognitive map produced by lay participants posits direct paths between causes and the target illness (stress), with no paths between different causes. The most frequently identified causes of stress were workload and personality (both endorsed by all participants). All causes were attributed medium strength (40-69), except for diet/exercise (mean strength of 34.6). Three potential causes were not identified by lay participants as being linked to the target illness or to other causes: age, sex, and ethnic background.

In contrast to the map produced by lay participants, the expert model specifies links from all potential causes to stress: including causal links from age, sex, and ethnic background. The expert model also posits inter-linkage of some causes: a two-way connection between workload and job dissatisfaction and a pathway from support/coping to domestic situation. These connections reflect the perception of indirect pathways from causes to the target illness. The most frequently identified causes of stress were personality, support/coping, workload and job dissatisfaction (all were endorsed by every participant); this differed from the lay model, wherein support/coping mechanisms and job dissatisfaction were not identified as causes by all participants. In the expert model, job dissatisfaction, domestic situation, and support/coping were in the high range of causal strength (70-100). Pathways to stress from personality and diet/exercise were in the medium range of strength (40-69), as was the pathway from workload to job dissatisfaction. All other connections - including paths from job dissatisfaction to workload and from support/coping to domestic situation - were in the low range (10-39).

4.4.4 Asthma Cognitive maps for asthma are shown in figure 12.

45 Figure 12 Lay (left) and expert (right) maps of perceived causal paths of asthma

The cognitive map produced by lay participants posits direct paths between causes and the target illness (asthma), with no paths between different causes. The most frequently identified cause of asthma was irritants (endorsed by all participants). All identified connections were in the medium range of strength (40-69) except for age and medical history (both in the lower range of 10-39). Two potential causes were not identified by lay participants as being linked to the target illness or to other causes: sex and ethnic background.

In contrast to the map produced by lay participants, the expert model posits inter-linkage of some causes as well as paths between causes and the target illness (asthma). Furthermore, the expert model specifies links from all potential causes to asthma: including causal links from sex and ethnic background. The most frequently identified cause of asthma was air pollution (endorsed by all participants); this differed from the lay model, wherein the influence of irritants was most popularly endorsed. All identified causes of asthma were in the medium range of strength (40-69) except for age, sex, ethnic background, and medical history (these were in the low range of 10-39). Perceived influential pathways between causes - from air pollution to irritants, from air pollution to allergies, and from irritants to allergies - were all in the lower range of strength.

4.5 INTERIM CONCLUSIONS

The cognitive structural maps show three main lay and expert differences. First, lay people were less willing to endorse demographic factors as contributing to the illnesses studied, however, age was cited as a cause of MS, lung cancer and asthma. What underlies this difference is not known from these data. Second, experts have more complex maps than lay participants. Only experts see links between the causes, whereas the lay participants view each cause as an independent predictor of each illness. Finally, where experts and lay participants agree on causes, experts see some of these causes as more important (e.g., work load and social support for stress).

4.6 GENERAL DISCUSSION AND IMPLICATIONS FOR EDUCATION AND TRAINING

One main finding to emerge from these analyses of perceived causes, is that experts do have a different conceptualisation to lay participants. Across both methods (illness representations and SCMs) the results suggest that (1) experts generally rate causes as being more important and (2) experts are more 46 likely to see work-related characteristics as more important causes of stress and lung cancer. There are implications for education and training here. First, it may be that it is by interacting with experts that certain causes are highlighted for lay participants, which may result in them labelling their illness as work-related. This is not to say that work may not be a contributing factor, but that experts should be made aware that their models of illness may in fact lead lay participants to particular explanations. The fact that lung cancer but not asthma is perceived as work related by experts is also somewhat puzzling given both are diseases involving the respiratory system, but the link between asthma and work characteristics is easier to determine than it is for lung cancer and work-characteristics.

47 5 TRUST IN SOURCES OF INFORMATION

This chapter addresses the following questions:

• What are the main sources of trusted information about occupational and non-occupational disease? • Which of these sources are seen as the most trustworthy by lay and expert groups and do these vary by disease type? • What is the relationship between sources of information and illness representation factors?

5.1 PERCEIVED TRUSTWORTHINESS OF INFORMATION SOURCES (ACROSS ILLNESSES AND EXPERTISE)

These analyses examined within-person rankings of information sources by trustworthiness (irrespective of individual differences in expertise). A one-way repeated-measures ANOVA was conducted on ratings of 8 different information sources. Scores for each resource reflect the perceived trustworthiness of their information across illnesses (higher scores indicate greater trust).

Table 13 shows the perceived trustworthiness of sources in rank order (from most trustworthy to least trustworthy). There was a significant main effect of source on perceived trustworthiness [F (7, 1934) = 1249.20, p<.001]. Bonferroni-adjusted multiple-comparisons indicated that all differences between sources were significant at p<.001 (range of significant mean differences: 0.20 – 2.98). When considering potential sources of illness information, individuals tended to be most trusting of GPs and least trusting of employers.

Table 13 Information sources ranked by perceived trustworthiness

Information source M (SD) GP 5.87 (1.25)

Occupational health professionals 5.47 (1.33)

HSE 4.66 (1.61)

Internet 4.21 (1.50)

Friends/Family 3.50 (1.57)

TV/Radio 3.29 (1.42)

Newspapers/Magazines 3.09 (1.40)

Employer 2.88 (1.40)

Participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”.

48 5.2 COMPARING LAY AND EXPERT PERCEIVED TRUSTWORTHINESS OF INFORMATION SOURCES (ACROSS ILLNESSES)

These analyses looked at general differences (across all 4 illnesses) in perceptions of source trustworthiness between lay and expert groups. A one-way MANOVA was conducted with information sources as dependent variables and expertise group as the independent variable. Figure 13 shows the means for all sources for ratings of trustworthiness by expert versus lay participants. There were significant differences between lay and expert groups in the perceived trustworthiness of: GPs [F (1, 1939) = 34.80, p<.001], the HSE [F (1, 1939) = 22.04, p<.001], employers [F (1, 1939) = 8.81, p=.003], and friends/family [F (1, 1939) = 15.03, p<.001]. Lay participants were more trusting of GPs and friends/family; experts were more trusting of the HSE and employers.

7 6 5 Lay 4 Expert 3

Trustworthiness 2 1 ls E t o ly a e i es GP S rn d n ion H s te /Fami azi s In g e TV/Ra ds Employer rof n P rie F alth apers/Ma e p al H n News

Occupatio Source

Participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”. Figure 13 Group differences in perceived trustworthiness of sources across illnesses (lay versus expert)

5.3 INTERIM CONCLUSIONS

When differences between lay and expert participants emerge, it is clear that lay participants judge GPs and friends and family as more trustworthy sources of information about the illnesses overall than experts. Experts, conversely judge the HSE and the employer to be more trustworthy sources of information than lay participants. Thus, again, expert and lay participants have different views and this again may have implications of expert-lay communications.

5.4 COMPARING LAY AND EXPERT PERCEIVED TRUSTWORTHINESS OF INFORMATION SOURCES (BY ILLNESS)

These analyses looked at differences between lay and expert groups in their perceptions of source trustworthiness for each illness (examined separately). For each illness, a one-way ANOVA was

49 conducted with information sources as dependent variables and expertise group as the independent variable.

5.4.1 Perceived trustworthiness of sources for MS information Compared with experts, lay people placed greater trust in GPs as a source of information about MS [F (1, 462) = 7.14, p=.008]. Figure 14 shows the means for this difference between groups. No other significant differences were found between lay and expert perceptions of resource trustworthiness.

Perceived trustworthiness of sources for MS

7 6 5 Lay 4 Expert 3

Trustworthiness 2 1 GP HSE HSE / / Internet Internet TV Radio Employer Employer ionals / Friends Family Profess Occupational Health Health Occupational Newspapers Magazines Source

Participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”. Figure 14 Group differences in perceived trustworthiness of sources for MS (lay versus expert)

5.4.2 Perceived trustworthiness of sources for lung cancer information Figure 15 shows mean differences between groups (lay versus expert) with regard to perceived trustworthiness of sources for lung cancer. Compared with lay people, experts placed greater trust in the HSE [F (1, 593) = 7.06, p=.008] and employers [F (1, 594) = 4.85, p=.028]. Lay people were relatively more trusting of friends/family [F (1, 595) = 5.64, P=.018]. No other significant differences were found between lay and expert perceptions of resource trustworthiness.

50 Perceived trustworthiness of sources for Lung Cancer

7 6 5 4 Lay 3 Expert

Trustworthiness 2 1 GP HSE HSE / / Internet Internet TV Radio Employer Employer ionals / Friends family Profess Occupational Health Health Occupational Newspapers Magazines Source

Participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”. Figure 15 Group differences in perceived trustworthiness of sources for lung cancer (lay versus expert)

5.4.3 Perceived trustworthiness of sources for stress information Figure 16 shows mean differences between groups (lay versus expert) with regard to perceived trustworthiness of sources for stress. Compared with experts, lay people placed greater trust in GPs [F (1, 547) = 18.79, p<.001] and friends/family [F (1, 540) = 17.16, p<.001]. Experts were relatively more trusting of the HSE [F (1, 528) = 13.43, p<.001]. No other significant differences were found between lay and expert perceptions of resource trustworthiness.

51 Perceived trustworthiness of sources for Stress

7 6 5 Lay 4 Expert 3

Trustworthiness 2 1 GP HSE HSE / / Internet Internet TV Radio Employer Employer ionals / i Friends family Profess Occupat onal Health Newspapers Magazines Source

Participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”. Figure 16 Group differences in perceived trustworthiness of sources for stress (lay versus expert)

5.4.4 Perceived trustworthiness of sources for asthma information Figure 17 shows mean differences between groups (lay versus expert) with regard to perceived trustworthiness of sources for asthma. Compared with experts, lay people placed greater trust in GPs [F (1, 489) = 6.17, p=.013] and friends/family [F (1, 489) = 5.08, p=.025]. Experts were relatively more trusting of the HSE [F (1, 478) = 10.08, p=.002]. These differences replicated those observed in relation to sources of information for stress. No other significant differences were found between lay and expert perceptions of resource trustworthiness.

52 Perceived trustworthiness of sources for Asthma

7 6 5 Lay 4 Expert 3

Trustworthiness 2 1 io GP HSE HSE Internet TV/Rad Employer Employer ionals / ends Fam Fri / ily Profess Occupational Health Health Occupational Newspapers Magazines Source

Participants rated the trustworthiness of each information source on a scale from 1 to 7, where 1 = “not at all trustworthy” and 7 = “definitely trustworthy”. Figure 17 Group differences in perceived trustworthiness of sources for asthma (lay versus expert)

5.5 INTERIM CONCLUSIONS

The above analyses show that in terms of the differences between expert and lay groups, lay participants were more likely to judge GPs and friends and family as more trustworthy sources of information than experts, whereas experts are more likely to judge the HSE and employers as more trustworthy than lay participants. Thus it seems that lay participants view inter-personal sources as more trustworthy and experts view external impersonal sources as offering more trustworthy information.

5.6 REGRESSING ILLNESS REPRESENTATIONS ONTO SOURCES

The influence of trusted information sources on representations about illness was examined using hierarchical multi-linear regression analyses. For each illness a separate equation was calculated with each illness representation factor (7 IPQ-R factors and 5 work-characteristics) as the dependent variable. For each illness 12 regressions were conducted. Expertise (0 = lay, 1 = expert) was controlled for at Step 1; information sources were entered at Step 2. Expertise was controlled at step 1 to adjust for any variability in illness-representation due to expertise. This analytical procedure was executed for each of the four illnesses. Results are presented in the following sub-sections. Initially the reliability of the IPQ-R factors was examined.

5.6.1 IPQ-R Factors – Reliability Analysis The 7 IPQ-R factor scores were derived from illness questionnaire items (Moss-Morris et al., 2002). These factors and their associated reliabilities and zero-order correlations are presented in Table 14.

53 Table 14 Reliability and inter-relation of illness representation factors

Correlations Illness Representation 1 2 3 4 5 6 α rii (1) Illness Coherence† (2) Timeline-acute/chronic -.21*** .67 .52 (3) Timeline-cyclical .08** .05* .58 .41 (4) Treatment Control .10*** -.09*** .12*** .54 .37 (5) Personal Control .20*** -.25*** -.04 .23*** .68 .52 (6) Emotion Representations -.01 .17*** .08*** -.16*** -.07** .70 .55 (7) Serious Consequences -.05* .24*** .04 -.23*** -.12*** .54*** .77 .63 * p<.05, ** p<.005, *** p<.001 †This factor was represented by a single item α = Cronbach’s alpha reliability; rii = inter-item correlation

These results show that all of the IPQ-R factors are reliable enough for group comparisons (i.e., alphas > .50; Helmstadter, 1964). These factors are then used as the DVs in the subsequent hierarchical regression analyses.

5.6.2 MS

5.6.2.1 MS: IPQ-R Factors Results are shown in Table 15. Controlling for expertise, trust in information sources only added significantly to models predictive of MS representations in terms of timeline (cyclical) and treatment control. Individuals with stronger representations of MS as being cyclical in symptom presentation over time tended to be more trusting of occupational health professionals and less trusting of friends/family. Those with stronger representations of MS as an illness that is controllable by treatment tended to place more trust in print media (newspapers/magazines).

Two further associations were observed between trust in sources and MS representations, though the predictive model of which they were a component (information sources at Step 2) did not reach significance overall. Respondents who had stronger representations of MS as an illness with negative emotional consequences tended to rely on the advice of employers, and those viewing MS as a condition with serious consequences tended to rely less on GP information. These associations must be interpreted cautiously given that they were not predicted a priori (it is more acceptable to look beyond the multivariate F when testing hypotheses relevant to particular bivariate associations).

54 Table 15 Regression of IPQ-R representations of MS onto trusted sources of information

Illness Timeline- Timeline- Treatment Personal Emotion Serious Coherence chronic cyclical Control Control Representations Consequences Step 1 Expertise .65*** -.12 .03 .01 .46** .07 -.04 (0 = Lay, 1 = Expert) R²† .03*** .00 .00 .00 .02** .00 .00 Step 2 GP -.05 .08 -.05 .06 .02 -.04 -.05* Internet .02 .00 .03 .00 -.06 .04 .02 HSE -.06 -.05 -.02 .05 .05 -.03 .02 Employer .02 .01 .03 -.03 .03 .10** .01 Friends/Family .00 -.01 -.09** -.03 -.06 -.02 .01 Occupational Health .02 -.01 .07* -.01 -.04 .00 .03 Professionals Newspapers/ Magazines -.02 -.03 .04 .15** .08 -.07 -.05 TV/Radio -.06 .05 -.04 -.10 -.06 .04 .04 R² .05 .03 .04* .04* .04* .04 .02 ∆R² .02 .03 .04* .04* .02 .03 .02 Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.6.2.2 MS: Occupation-related beliefs Results are shown in Table 16. After controlling for expertise, three associations emerged between occupational representations and trusted sources. Those with a stronger belief that MS sufferers should inform their employer were generally more trusting of GPs and occupational health professionals. Those who had a stronger belief in the employer’s responsibility to protect workers (from conditions that may worsen symptoms of MS) placed greater trust in occupational health professionals. However, this last association was not part of a significant predictive model.

Table 16 Regression of work-related representations of MS onto trusted sources of information

Employer Advise Cause should not to do Stop work days off Should tell protect certain permanently work employer sufferer jobs Step 1 Expertise -.53*** -.22 -.54*** -.09 -.15 (0 = Lay, 1 = Expert) R²† .03 .01 .05*** .00 .00 Step 2 GP .00 -.02 .09** .02 -.01 Internet -.02 -.04 -.01 .02 .00 HSE .04 .05 -.01 .02 .04 Employer .00 .02 .02 .01 .07 Friends/Family .04 -.02 -.03 -.03 -.05 Occupational Health -.01 .00 .07* .06* .04 Professionals Newspapers/Magazines -.07 -.04 .04 .02 .02 TV/Radio .05 .05 .00 .03 -.03 R² .04 .03 .10*** .04 .03 ∆R² .01 .02 .05** .03 .02 Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

55 5.6.3 Lung Cancer

5.6.3.1 Lung cancer: IPQ-R Factors Results are shown in Table 17. Controlling for expertise, trust in information sources only added significantly to models predictive of lung cancer representation in terms of treatment control. Those with stronger representations of lung cancer as an illness that is controllable by treatment tended to place more trust in occupational health professionals; they were less trusting of information from friends/family and TV/radio broadcasts.

One further association was observed between trust in sources and lung cancer representations, though the predictive model of which it was a component (information sources at Step 2) did not reach significance overall and therefore this association must be treated cautiously. Respondents who viewed lung cancer as a chronic illness tended to rely more on HSE information.

Table 17 Regression of IPQ-R representations of lung cancer onto trusted sources of information

Illness Timeline- Timeline- Treatment Personal Emotion Serious Coherence chronic cyclical Control Control Representations Consequences Step 1 Expertise .67*** -.03 -.04 -.01 .45*** .13 -.07 (0 = Lay, 1 = Expert) R²† .04*** .00 .00 .00 .02*** .00 .00 Step 2 GP -.05 .03 -.01 .01 -.01 .02 .01 Internet .07* -.03 -.01 .02 -.04 -.02 -.01 HSE -.01 .06* .02 -.03 .02 .04 .02 Employer -.03 -.01 .02 .01 -.02 -.01 -.01 Friends/Family .06 -.01 -.01 -.05* -.01 -.03 -.02 Occupational Health .06 .00 .01 .08** .00 .01 .01 Professionals Newspapers/ Magazines -.07 -.07 -.01 .07 -.01 -.03 -.04 TV/Radio .03 .08 -.02 -.09* .08 .06 .07 R² .06*** .03 .01 .03* .04* .03 .02 ∆R² .02 .03 .01 .03* .01 .02 .02 Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.6.3.2 Lung cancer: Occupation-related beliefs Results are shown in Table 18. After controlling for expertise, four associations emerged between occupational representations and trusted sources. Those who had a stronger belief in the employer’s responsibility to protect workers (from conditions that may worsen symptoms of lung cancer) placed greater trust in the HSE and occupational health professionals. Those of the view that lung cancer sufferers should be advised not to do certain jobs were more trusting of the HSE. Those with a stronger belief that lung cancer sufferers would have to stop work permanently were generally more trusting of GPs. However, these last two associations was not part of overall-significant predictive models.

56 Table 18 Regression of work-related representations of lung cancer onto trusted sources of information

Employer Advise Cause should not to do Stop work days off Should tell protect certain permanently work employer sufferer jobs Step 1 Expertise -.26 -.08 -.27* .15 .03 (0 = Lay, 1 = Expert) R²† .00 .00 .01* .00 .00 Step 2 GP .09* .04 .05 .01 .01 Internet .01 -.01 -.01 -.02 -.01 HSE .02 .02 -.02 .06** .06* Employer -.03 .00 .05 .02 .00 Friends/Family .06 .00 -.04 -.02 .00 Occupational Health .00 .03 .00 .05* .06 Professionals Newspapers/Magazines -.02 -.03 -.03 -.02 -.05 TV/Radio -.02 .04 .05 .05 .02 R² .02 .02 .02 .06*** .03 ∆R² .02 .02 .01 .06*** .03* Unstandardised beta coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.6.4 Stress

5.6.4.1 Stress: IPQ-R Factors Results are shown in Table 19. Controlling for expertise, trust in information sources added significantly to models predictive of stress representations in terms of treatment control, personal control, emotion representations and serious consequences. Those with stronger representations of stress as is controllable by treatment tended to place more trust in occupational health professionals. Those who perceived stress as being under personal control were less trusting of their GP and friends/family, but more trusting of occupational health professionals. Respondents who had stronger representations of stress as having negative emotional consequences tended to rely less on the advice of employers; they were more trusting of GPs and friends/family. Stress was viewed as having more serious consequences by individuals who were more trusting of the internet as an information source.

Two further associations were observed between trust in sources and a representation of stress, though the predictive model of which they were a component (information sources at Step 2) did not reach significance overall and these associations must be interpreted cautiously. Respondents who had stronger representations of stress as a cyclical condition tended to rely more on the advice of friends/family, and less on newspapers/magazines.

57 Table 19 Regression of IPQ-R representations of stress onto trusted sources of information

Illness Timeline- Timeline- Treatment Personal Emotion Serious Coherence chronic cyclical Control Control Representations Consequences Step 1 Expertise .51*** -.33** -.25** .07 .34*** -.16* -.27*** (0 = Lay, 1 = Expert) R²† .03*** .02** .02** .00 .03*** .01* .03*** Step 2 GP -.06 .02 .01 -.05 -.09*** .05* .01 Internet .01 -.02 -.03 .01 .03 .03 .05* HSE -.03 .02 .02 .02 .02 .02 -.01 Employer .02 .01 .02 .05 -.01 -.05* -.01 Friends/Family .04 .01 .04* .02 -.08*** .06** .04 Occupational Health .05 .01 -.03 .06* .07* .00 .04 Professionals Newspapers/ Magazines .10 -.06 -.10* -.04 .02 -.06 -.05 TV/Radio -.09 .04 .06 -.03 -.05 .03 .02 R² .05** .04* .04* .04* .10*** .05** .06** ∆R² .02 .01 .03 .04* .07*** .05** .03* Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.6.4.2 Stress: Occupation-related beliefs Results are shown in Table 20. After controlling for expertise, eight associations emerged between occupational representations and trusted sources. Those with a stronger belief that stress sufferers would have to take days off work were generally more trusting of broadcast media and less trusting of print media. Those who believe strongly that a person with stress should inform their employer were more inclined to trust employers and their friends/family. Those who had a stronger belief in the employer’s responsibility to protect workers (from conditions that may worsen symptoms of stress) placed greater trust in the HSE and friends/family. Finally, those of the view that stress sufferers should be advised not to do certain jobs were more trusting of broadcast media and less trusting of print media. However, these two associations did not form part of a significant predictive model.

58 Table 20 Regression of work-related representations of stress onto trusted sources of information

Employer Advise Cause should not to do Stop work days off Should tell protect certain permanently work employer sufferer jobs Step 1 Expertise -.16 -.21 -.03 .08 -.08 (0 = Lay, 1 = Expert) R²† .01 .01 .00 .00 .00 Step 2 GP -.03 .05 .03 -.02 .01 Internet .04 -.02 .02 .04 .02 HSE -.04 .01 .00 .12*** -.02 Employer .03 .03 .13*** .01 .03 Friends/Family .03 .02 .08** .08** .04 Occupational Health -.04 .00 .05 .01 -.01 Professionals Newspapers/Magazines -.02 -.16** -.09 -.05 -.12* TV/Radio .01 .13* -.01 -.01 .12* R² .03 .04* .09*** .07*** .02 ∆R² .02 .03* .09*** .07*** .02 Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.6.5 Asthma

5.6.5.1 Asthma: IPQ-R Factors Results are shown in Table 21. Controlling for expertise, trust in information sources only added significantly to models predictive of asthma representations in terms of timeline (cyclical) and treatment control. Individuals with stronger representations of asthma as being cyclical in symptom presentation over time tended to be more trusting of employers. Those with stronger representations of asthma as an illness that is controllable by treatment tended to place more trust in occupational health professionals.

Two further associations were observed between trust in sources and representations of asthma, though the predictive model of which they were a component (information sources at Step 2) did not reach significance overall and therefore these associations must be interpreted cautiously. Respondents who had stronger representations of asthma in terms of negative emotional consequences trusted the HSE more. Those who had stronger representations of asthma in terms of serious consequences trusted TV/radio broadcasts more.

59 Table 21 Regression of IPQ-R representations of asthma onto trusted sources of information

Illness Timeline- Timeline- Treatment Personal Emotion Serious Coherence chronic cyclical Control Control Representations Consequences Step 1 Expertise .06 .11 .16 .06 .23* -.06 .11 (0 = Lay, 1 = Expert) R²† .00 .00 .01 .00 .01* .00 .00 Step 2 GP -.01 .04 -.04 .03 .02 -.03 -.03 Internet .01 .05 .01 -.01 -.01 .00 .04 HSE -.02 .02 .01 .02 .03 .06* .05 Employer -.03 -.03 .07* -.03 -.03 .00 -.06 Friends/Family .04 .05 -.03 -.03 -.05 .00 .04 Occupational Health .05 -.02 .06 .08** .04 -.04 -.02 Professionals Newspapers/Magazines -.06 .01 .01 -.01 .05 .04 -.10 TV/Radio .05 -.02 -.01 .04 -.04 .01 .13* R² .01 .02 .04* .05* .04 .03 .03 ∆R² .01 .02 .04* .05* .02 .03 .03 Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.6.5.2 Asthma: Occupation-related beliefs Results are shown in Table 22. After controlling for expertise, six associations emerged between occupational representations and trusted sources. Those with a stronger belief that asthma sufferers would have to give up work were generally more trusting of friends/family, although this association did not form part of a significant predictive model (above and beyond prediction by expertise). Those who believe strongly that a person with asthma should inform their employer were more inclined to trust GPs. Those who had a stronger belief in the employer’s responsibility to protect workers (from conditions that may worsen symptoms of asthma) placed greater trust in the HSE and occupational health professionals. Finally, those of the view that asthma sufferers should be advised not to do certain jobs were also more trusting of the HSE and occupational health professionals.

60 Table 22 Regression of work-related representations of asthma onto trusted sources of information

Employer Advise Cause should not to do Stop work days off Should tell protect certain permanently work employer sufferer jobs Step 1 Expertise -.23* -.24 -.12 -.04 (0 = Lay, 1 = Expert) R²† .01* .01 .00 .00 .00 Step 2 GP -.05 -.02 .14** .05 .02 Internet .03 .04 .01 -.02 .03 HSE .00 .02 .02 .10*** .08* Employer .04 -.03 .01 -.05 -.04 Friends/Family .07* .07 -.01 -.01 .01 Occupational Health -.02 .08 .07 .09** .09* Professionals Newspapers/Magazines -.03 -.06 .05 -.05 .02 TV/Radio .00 .03 -.09 .01 -.03 R² .04* .04 .06** .09*** .05* ∆R² .03 .03 .06** .09*** .05** Unstandardised Β coefficients are shown for all relationships. Discrepancies between R² at each step and ∆R² reflect rounding. † Variance accounted for (range 0-1) *p<.05, **p<.01, ***p<.001

5.7 DISCUSSION

There are a number of conclusions that can be drawn from these analyses. First, there are more associations with stress than each of the other illnesses. Second, friends and family, GPs, HSE and the employers are also sources that are more likely to be associated with illness representation dimensions and work-characteristics. Third, with respect to the work-related job-characteristics, trust in the HSE, and occupational physicians was related to work-related practical advice about work relationships (e.g., not to do certain jobs) whereas trust in GPs and family and friends were associated with more inter personal actions – for example stopping working, informing their employer. Finally, the role of the mass media was only evident for representations of stress – again this may imply a cultural aspect to the interpretation of stress and how to respond to it.

61 6 THE ROLE OF RAW AND CALIBRATED KNOWLEDGE

The following questions are addressed in this chapter:

• Are lay and expert groups under- or over-confident with respect to knowledge about MS, asthma, lung cancer and stress? • To what extent is the degree of knowledge calibration related to illness representation factors for lay and expert groups (do people who are better calibrated see diseases as having more or less severe consequences or different causes) for each illness?

6.1 COMPARING LAY AND EXPERT KNOWLEDGE, CONFIDENCE, AND CALIBRATION

6.1.1 Factual illness knowledge These analyses examined whether expert and lay groups differed in their performance on questions testing objective knowledge relevant to each illness (examined separately). For each illness, a one-way ANOVA was conducted with mean percentage performance as the dependent variable and expertise group as the independent variable. Scores reflect response accuracy (higher scores are indicative of greater knowledge performance).

Figure 18 shows mean percentage performance scores for expert and lay groups. Separate means are shown for each of the 4 illnesses. Analyses indicated that there were significant performance differences between expert and lay groups for lung cancer [F (1, 610) = 38.63, p<.001] and asthma [F (1, 496) = 19.51, p<.001]. Compared with lay respondents, experts were generally more knowledgeable in their responses to questions relevant to these illnesses. There was a similar marginal differences between groups in their performance on questions pertaining to stress [F (1, 551) = 3.62, p=.058]. Groups did not differ significantly in their performance on questions related to MS.

62 Knowledge question performance by illness

100

95

90

85

80 Lay 75 Expert 70

65 Percentage correct 60

55

50 MS Lung Stress Asthma Cancer Illness

Figure 18 Group differences in illness knowledge (lay versus expert)

6.1.2 Confidence in illness knowledge The following analyses examined whether expert and lay groups differed in the extent to which they were confident about their answers to objective knowledge questions for each illness (examined separately). For each illness, a one-way ANOVA was conducted with mean confidence score as the dependent variable and expertise group as the independent variable. Scores reflect confidence in knowledge (higher scores are indicative of greater self-belief).

Figure 19 shows mean scores for expert and lay confidence about knowledge responses. Separate means are shown for each of the 4 illnesses. Analyses indicated that there were significant confidence differences between groups for MS [F (1, 454) = 41.79, p<.001], lung cancer [F (1, 584) = 19.37, p<.001], and stress [F (1, 522) = 13.99, p<.001]. Experts tended to have relatively greater confidence in their answers to knowledge questions relevant to these illnesses. Groups did not differ significantly in their confidence about asthma-related knowledge-responses.

63 Confidence in knowledge question performance by illness

100

95 90

(%) (%) 85

80 Lay 75 Expert 70

65

Average confidence confidence Average 60 55

50 MS Lung Stress Asthma Cancer Illness

Scores represent percentage certainty regarding the accuracy of answers to illness knowledge questions Figure 19 Group differences in illness knowledge confidence (lay versus expert)

6.1.3 Knowledge calibration A knowledge calibration score was also calculated by comparing the degree of actual accuracy (percentage correct) with the perceived level of accuracy (confidence). A positive coefficient indicates overconfidence (participants think they know more than they actually do), a negative score indicates under-confidence (participants know more than they actually think they do) and zero indicates perfect calibration (participants know what they think they know).

Present analyses compared expert and lay knowledge calibration for each illness (analysed separately). For each illness, a one-way ANOVA was conducted with knowledge calibration as the dependent variable and expertise group as the independent variable.

Figure 20 shows mean calibration for expert and lay groups. Separate means are shown for each of the 4 illnesses. Analyses indicated that there were significant calibration differences between lay and expert groups for knowledge about MS [F (1, 454) = 18.22, p<.001] and asthma [F (1, 468) = 4.52, p=.034]. In their responses to questions about MS, experts showed a tendency to be overconfident and lay respondents showed a tendency to be under-confident. These contrasting tendencies were found to be significantly different in magnitude. Conversely, in responses to questions about asthma, it was lay people who demonstrated general overconfidence, whereas experts tended towards under-confidence. Groups did not differ significantly in their calibration for lung cancer or stress.

64 Knowledge calibration by illness

15

10

5 ( )

Lay 0 Expert MS Lung Cancer Stress Asthma

-5 % under% Calibration over % ()-10

-15 Illness

A score of 0 represents calibration (knowledge = confidence in knowledge). Scores above 0 are indicative of overconfidence, scores below 0 are indicative of under-confidence. Scores differing from 0 are represented as percentage under-/over-confidence. Figure 20 Group differences in illness knowledge calibrations (lay versus expert)

6.2 INTERIM CONCLUSIONS

The results of these analyses show that, indeed, experts are more knowledgeable but only for medically well known illnesses (lung cancer and asthma), and in general were more confident. However, this confidence might be misplaced as experts were not perfectly calibrated. For MS, experts were over confident (thought that they knew more than they actually did) compared to lay participants, but were under-confident for asthma (knew more than they thought they did). The lay participants showed the opposite pattern. Both groups were under-confident with respect to their knowledge about stress.

6.3 ASSOCIATIONS BETWEEN ILLNESS REPRESENTATIONS AND KNOWLEDGE CALIBRATION

Present analyses examined zero-order correlations between representations of illness (IPQ-R factors and work-related job characteristics) and degree of knowledge calibration. These analyses were carried out separately for each illness type/group.

For MS, there was a significant positive association between illness coherence and knowledge calibration (r = .15, p=.002). Those who perceived that they had a greater understanding of MS also tended to be over-confident in their knowledge. This association between illness coherence and knowledge calibration was also evident for lung cancer (r = .17, p<.001).

65 A second association was observed for lung cancer between knowledge calibration and the belief that sufferers should be advised not to do certain jobs (r = .17, p<.001) Those who were more convinced of the need to advise sufferers against particular occupational practices also tended towards over confident in their illness knowledge.

For stress, associations were observed between knowledge calibration and (1) personal control (r = .09, p=.041) and (2) the belief that stress would cause absenteeism (r = .09, p=.034). The nature of these associations was such that the more over-confident in their illness knowledge that individuals were (1) the more they perceived stress to be controllable by the actions of the sufferer and (2) the more they perceived stress as a cause of absenteeism. No associations between illness representations and knowledge calibration were observed for asthma.

6.4 INTERIM CONCLUSIONS

The results show that over-confidence in knowledge is related to illness representations. However, no clear pattern emerged with respect to illness representation dimensions.

6.5 GENERAL DISCUSSION

These results show that experts and lay participants differ with respect to their levels of knowledge, confidence and calibration. That is, neither group is calibrated: for MS, experts are over-confident and lay participants under-confident, and the reverse is true for asthma. The degree of over-confidence, not under-confidence is related to the illness representation dimensions.

66 7 ILLNESS REPRESENTATIONS FOR THE FOUR DISEASES

This chapter addresses the following question: • Do experts and the lay public have similar models (e.g., time line, treatment, consequences etc.) and symptom profiles for the diseases?

7.1 COMPARING LAY AND EXPERT ILLNESS REPRESENTATIONS (BY ILLNESS)

These analyses looked at differences between lay and expert groups in their representations of each illness (examined separately). For each illness, a one-way ANOVA was conducted with illness representations (the 7 factors from the IPQ-R and 5 additional items reflecting the consequences of the illness on work related behaviour) as dependent variables and expertise group as the independent variable. Scores for each representation reflect their concordance with participants’ beliefs about the illness in question (higher scores indicate greater agreement with this view/representation).

7.1.1 Representations of MS Figure 21 shows significant mean differences in MS representations between groups (lay versus expert). Experts had stronger representations of MS in terms of illness coherence [F (1, 456) = 13.80, p<.001] and personal control [F (1, 448) = 8.83, p=.003]. Compared with lay participants, they perceived MS to be more understandable and more reactive to the sufferer’s behaviour. Lay participants gave greater endorsement to statements suggesting that people with MS would have to stop working permanently [F (1, 461) = 14.05, p<.001] and should inform their employers of their illness [F (1, 461) = 17.59, p<.001]. No other differences were found between expert and lay representations of this illness.

MS representations

5

4 Lay 3 Expert

Agreement 2

1 l l ic l i lness Contro Il work work employer Treatment Treatment Should tell tell Should Stop work work Stop Coherence Coherence Serious i permanently permanently Emot on certain jobs certain meline-cyclica Cause days Causeoff days meline-chron Consequences Advse not to do Advse to not protect sufferer sufferer protect Ti Representations Representations Ti Personal Contro Employer should Employer Illness representation

Scores reflect agreement with each representation of MS on a scale from 1 to 5, where 1 = “strongly disagree” and 5 = “strongly agree”. Figure 21 Group differences in illness representations for MS (lay versus expert)

67 7.1.2 Representations of lung cancer Figure 22 shows significant mean differences in lung cancer representations between groups (lay versus expert). Experts had stronger representations of lung cancer in terms of illness coherence [F (1, 598) = 24.12, p<.001] and personal control [F (1, 597) = 15.05, p<.001]. Compared to lay participants, experts perceived lung cancer to be more understandable and more reactive to the sufferer’s behaviour. Lay participants gave greater endorsement to statements suggesting that people with lung cancer would have to stop working permanently [F (1, 603) = 4.08, p=.044] and should inform their employers of their illness [F (1, 608) = 4.55, p=.033]. This pattern of differences replicated that observed between representations of MS. No other differences were found between expert and lay representations of this illness.

Lung Cancer representations

5

4 Lay 3 Expert

Agreement Agreement 2

1 l ic l i lness Contro Il work work employer Treatment Treatment Should tell tell Should Coherence Coherence Stop work work Stop Serious i permanently permanently Emot on certain jobs certain meline-cyc ical meline-chron Cause days Causeoff days Consequences Advse not to do Advse to not protect sufferer sufferer protect Ti l Ti Representations Representations Personal Contro Employer should Employer Illness representation

Scores reflect agreement with each representation of lung cancer on a scale from 1 to 5, where 1 = “strongly disagree” and 5 = “strongly agree”. Figure 22 Group differences in illness representations for lung cancer (lay versus expert)

7.1.3 Representations of stress Figure 23 shows significant mean differences in stress representations between groups (lay versus expert). Experts had stronger representations of stress in terms of illness coherence [F (1, 534) = 20.12, p<.001] and personal control [F (1, 534) = 9.25, p<.001]. Again, compared to lay participants, experts perceived stress to more understandable and more reactive to the sufferer’s behaviour. Lay participants had stronger representations of stress as a condition with a chronic [F (1, 533) = 9.75, p=.002] and cyclical [F (1, 531) = 10.25, p=.001] timeline. Compared to experts, lay participants perceived stress to be longer lasting and more variable in its symptom presentation from day to day. Lay participants also gave relatively greater endorsement to statements suggesting that people with stress would have to stop working permanently [F (1, 543) = 4.73, p=.030]. No other differences were found between expert and lay representations of this illness.

68 Stress representations

5

4 Lay 3 Expert

Agreement Agreement 2

1 l l i lness ious ious Contro Il work work employer Treatment Treatment Should tell tell Should Stop work work Stop Coherence Coherence Ser i permanently permanently Emot on certain jobs certain meline-cyc ical meline-chronic meline-chronic Causeoff days Consequences Adv se not to do protect sufferer sufferer protect Ti l Ti Representations Representations Personal Contro Employer should Employer Illness representation

Scores reflect agreement with each representation of stress on a scale from 1 to 5, where 1 = “strongly disagree” and 5 = “strongly agree”. Figure 23 Group differences in illness representations for stress (lay versus expert)

7.1.4 Representations of asthma Figure 24 shows significant mean differences in asthma representations between groups (lay versus expert). Experts had a stronger representation of asthma in terms of personal control [F (1, 478) = 6.10, p=.014]. Compared to lay participants, experts perceived asthma to be more reactive to the sufferer’s behaviour. Lay participants gave relatively greater endorsement to a statement suggesting that people with asthma would have to stop working permanently [F (1, 493) = 5.58, p=.019]. No other differences were found between expert and lay representations of this illness.

69 Asthma representations

5

4 Lay 3 Expert

Agreement Agreement 2

1 l l l i lness ious Contro Il work work emp oyer Treatment Treatment Should tell tell Should Stop work Coherence Coherence Ser i permanently permanently Emot on certain jobs certain meline-cyc ical Cause days off Causeoff days meline-chronic meline-chronic Consequences Advse not to do Advse to not protect sufferer sufferer protect Ti l Representations Representations Ti Employer should Employer Personal Contro Illness representation

Scores reflect agreement with each representation of asthma on a scale from 1 to 5, where 1 = “strongly disagree” and 5 = “strongly agree”. Figure 24 Group differences in illness representations for asthma (lay versus expert)

7.2 INTERIM CONCLUSIONS

The results presented above may be summarised as follows. First, for MS, lung cancer, stress and asthma, experts were more likely than lay participants to endorse general illness representations of coherence and control, whereas lay participants were more likely to endorse effects on work. Specifically, lay participants, compared to experts, were more likely to endorse the idea that as a consequence of being diagnosed with any of the 4 illnesses a person should stop work permanently. However, it must be noted, that while this represents a difference between experts and lay participants, in absolute terms this was not the most highly endorsed work related consequence – in fact it was always the lowest.

Second, for stress, lay participants were more likely, compared to experts to see this as cyclical and chronic.

7.3 COMPARING LAY AND EXPERT PERCEPTIONS OF SYMPTOM SEVERITY/ILLNESS IDENTITY (BY ILLNESS)

These analyses looked at differences between lay and expert groups in their perceptions of symptom severity for each illness (examined separately). For each illness, a one-way ANOVA was conducted with symptom experiences as dependent variables and expertise group as the independent variable. Scores for each symptom reflect their perceived presence/severity in persons with the illness in question (higher scores indicate more severe symptom experiences).

7.3.1 Perceived symptoms of MS Figure 25 shows mean differences between groups (lay versus expert) with regard to perceived symptoms of MS. Compared with experts, lay participants rated the following experiences as being more severe: decreased mobility [F (1, 454) = 6.31, p=.012], breathlessness [F (1, 440) = 12.71, 70 p<.001], and pain [F (1, 456) = 7.69, p=.006). Experts gave a relatively higher estimate of presence/severity to the symptom of visual disturbance [F (1, 447) = 5.04, p=.025]. No other significant differences were found between lay and expert symptom ratings.

Perceived symptoms of MS

5

4

Lay 3 Expert Severity Severity 2

1

y e e gh ion it ue c bil g Pain nc ati ban ba Anxiety Cou ress F d Mo istur Headache Dep ase D re p Distur c Breathlessness ual e is lee D V S Symptom

Participants rated a sufferer’s average experience of each symptom on a scale from 0 to 5, where 0 = “not at all” and 5 = “would experience these symptoms severely”. Figure 25 Group differences in perceived severity of MS symptoms (lay versus expert)

7.3.2 Perceived symptoms of lung cancer Figure 26 shows mean differences between groups (lay versus expert) with regard to perceived symptoms of lung cancer. Compared with experts, lay participants rated the following experiences as being more severe: decreased mobility [F (1, 588) = 3.97, p=.047], breathlessness [F (1, 596) = 7.02, p=.008], and pain [F (1, 593) = 11.01, p=.001]. Experts gave a relatively higher estimate of presence/severity to the symptom of anxiety [F (1, 590) = 4.54, p=.034]. No other significant differences were found between lay and expert symptom ratings.

71 Perceived symptoms of Lung Cancer

5

4

Lay 3 Expert Severity Severity 2

1

y e gh lit ue c he ce i g c n ou Pain Anxiety C ob sness ati ban da M s F d istur Hea isturba Depressionse l D rea a p D Breathle ec isu D V Slee Symptom

Participants rated a sufferer’s average experience of each symptom on a scale from 0 to 5, where 0 = “not at all” and 5 = “would experience these symptoms severely”. Figure 26 Group differences in perceived severity of lung cancer symptoms (lay versus expert)

7.3.3 Perceived symptoms of stress Figure 27 shows mean differences between groups (lay versus expert) with regard to perceived symptoms of stress. Compared with experts, lay participants rated depression [F (1, 532) = 8.57, p=.004] and decreased mobility [F (1, 515) = 6.41, p=.012] as more severe symptoms. No other significant differences were found between lay and expert ratings of stress experiences.

72 Perceived symptoms of Stress

5

4

Lay 3 Expert Severity Severity 2

1

ty in e e e ility ss a nc xi sion b P anc ne ba b An Cough es Fatigue adache e epr H D eathless r ep Distur B e Decreased Mo Visual Distur Sl Symptom

Participants rated a sufferer’s average experience of each symptom on a scale from 0 to 5, where 0 = “not at all” and 5 = “would experience these symptoms severely”. Figure 27 Group differences in perceived severity of stress symptoms (lay versus expert)

7.3.4 Perceived symptoms of asthma Figure 28 shows mean differences between groups (lay versus expert) with regard to perceived symptoms of asthma. There were no significant mean differences between groups (lay versus expert) with regard to perceived symptoms of asthma.

Pe rce iv e d symptoms of Asthma

5

4

Lay 3 Expert Severity Severity 2

1

n e e lity i i a nc b ess P anc nxiety ssion n ba b A Cough e Fatigue adache e epr H D sed Mo a eathless re r ep Distur c B e De Visual Distur Sl Symptom

Participants rated a sufferer’s average experience of each symptom on a scale from 0 to 5, where 0 = “not at all” and 5 = “would experience these symptoms severely”. Figure 28 Group differences in perceived severity of asthma symptoms (lay versus expert) 73 8 EVALUATION OF THE DEVELOPED COGNITIVE MAPS

8.1 EXPERT FEEDBACK

To evaluate and cross-validate the cognitive maps developed from Main Study 3, expert participants in Main Study 3 were approached to comment on the final models. Five experts from the original sample provided semi-structured feedback.

Expert participants indicated that they considered the developed models could be useful as a communicative aid to doctor-patient interactions: the average rating of usefulness was 5.8 (SD = .84) on a scale from 1 (not useful at all) to 7 (extremely useful). All but one of the expert respondents indicated that they would use the models in practice, to assist their communication with patient groups. When asked how the models might be used in this way, all the experts referred to two related qualities: (1) models compare expert and lay illness perspectives in a way that encourages ‘reciprocal understanding’, and (2) information is presented in a ‘simple’ ‘visual framework’ that is ‘easy to digest’ and ‘clearly highlights’ important factors/differences. In terms of specific implications of these qualities, it was stressed that models could be used to inform lay individuals about their ‘gaps in knowledge’ and teach them to view ‘causes as interacting factors’. Further comments suggested that, when communicating with patients, experts should emphasise causal factors that are perceived as weaker in the lay versus expert model (to facilitate ‘more educated risk judgements’). One individual commented that the similarities between lay and expert representations should not be ignored either: ‘the amount of overlap shows that patients do have a good understanding…[they] should not be patronised’.

When asked for general comments and advice for how the models might be improved, expert respondents suggested that more specific information in parts of the models would ‘improve clarity’. For example, the causal influence of sex might be better communicated if the perceived nature of this relationship was indicated (‘are men or women more at risk?’). Questions were also raised about the ‘comprehensiveness’ of the named causal factors and it was suggested that similar models might be constructed to compare perceived ‘effects of the illness’ and potential ‘treatment alternatives’.

8.2 LAY FEEDBACK

Feedback on the cognitive maps was also obtained from 7 members of the lay public, who had not participated in the research previously. These participants indicated that they viewed the models as potentially useful aids to doctor-patient interaction: their average rating of usefulness on the 7-point scale was 5.14 (SD = .69). When asked about how the maps might be used to aid doctor patient communication, responses again centred on their facility to simply ‘show different perspectives’ so as to encourage ‘better understanding’. All participants commented on the clear graphical illustration of the different representations. One participant suggested that doctors could use lay representations to identify causal factors that may not be considered important by patients, and ‘ask specific questions relating to these’ factors (to gain information that might not otherwise be volunteered). Five of the respondents made comments to the effect that expert maps would serve the public as ‘a quick guide’ to the professional perception of ‘the most important risk factors’. It was suggested that such guidance would be especially useful where it highlights contributory factors that might be ‘controllable/avoidable’. 74 In terms of general comments, it was suggested by one individual that lay people might have heard about demographic differences in illness risk, but might ignore this information or be reluctant to report it because they are sensitive to issues of gender, ethnicity, or age - and they ‘don’t have the first-hand experience’ (of experts) to feel justified in making related attributions. Other comments were similar to those obtained from experts: suggesting that more detail could improve the models; although one individual cautioned that too much information would undermine the ‘ease-of-use’ of the models by making them ‘too complex’.

75 9 FINAL CONCLUSIONS AND RECOMMENDATIONS

9.1 CONCLUSIONS

There are a number of main conclusions that can be taken from these analyses that address how lay and expert groups structure their knowledge and beliefs about illness with respect to work and other causes. This has implications for communication between experts and lay groups and practical implications are drawn about how such information might be used.

The main findings and their theoretical implications are discussed below.

9.1.1 Illness caused by work People distinguish between illnesses that they believe to be derived from occupational and non occupational factors. In particular it would appear that the non-occupational illnesses tend to represent those for which there is a medical explanation (e.g., MS, lung cancer) and occupational illness a mixture of medically explainable (e.g., asbestosis) and unexplainable (e.g., stress). These attributional findings are consistent with recent evidence that occupational medicine is witnessing a rise in illnesses characterised by non-specific symptoms and more illness for which there is, as yet, no medical explanation (Coggon, 2005; Wessely, 2005).

9.1.2 Lay and expert differences Lay and expert groups differ with respect to perceived causes of illness, trust in sources of information, knowledge and representations of illness

9.1.2.1 Perceived causes Results from both the cognitive maps and the field based experiment showed that experts have more complex representations of the causes of illness. This is seen both in terms of the inter-connectedness of causal links (cognitive maps) and the stronger endorsement of causes regardless of the illness and for specific illnesses. This pattern of results is wholly consistent with the previous findings on expert and lay differences reported in the general psychology literature. While this general pattern of results confirms most findings about expert-lay differences, the pattern of differences is of particular importance for occupational health. For the more medically explained illnesses (MS and Asthma) expert and lay participants differed with respect to which they attributed non-work related factors as causes of these illnesses (e.g., altered immunity). Thus while both groups might perceive work related factors as a cause it is only for non-work related factors that there are perceived differences. However, for stress, which is less medically explainable, experts were more likely to attribute work related factors as a cause than lay participants. This is not to say that lay participants do not see work as a causal factor in the experience of stress – indeed the means in Figure 7 suggest that lay participants perceive work factors as an important causal factor in the experience of stress - it is just that experts perceive the causal role of work related factors as stronger. Thus expert and lay groups differ with respect to the strength to which they endorse work and non-work related causes as a factor in the experience of stress and medically explained illnesses.

9.1.2.2 Sources of information Overall lay participants were more likely to trust inter-personal sources of information (friends, GPs) and experts impersonal sources (HSE, employers). The higher perceived trust in inter-personal sources 76 of information replicates previous findings (Ferguson et al., 2004). However, it is of note that one of the sources of trusted inter-personal information by lay participants are GPs – a group which might be considered an expert group. As such, lay participants have greater trust in experts as providing a trustworthy source of information on illness, occupational or otherwise.

9.1.2.3 Knowledge Experts tended to know more about asthma and lung cancers (medically explained) and were marginally more knowledgeable about stress. However, along with the lay participants they were not perfectly calibrated in terms of their knowledge – that is participants were sometimes over confident (knew less than they thought they did) or under confident (knew more than they thought they did). It has been suggested that this might reflect anxiety of the nature of a changing knowledge base (Ferguson et al., 1995)

9.1.2.4 Work-related consequences Expert and lay groups also differed with respect to the perceived consequences with respect to working life for each of the illnesses. Specifically, lay participants, compared to experts, were more likely to endorse the idea that as a consequence of any of the 4 illness a person diagnosed should stop work permanently. However, it must be noted, that while this represents a difference between experts and lay participants, in absolute terms this was not the most highly endorsed work related consequence – in fact it was always the lowest. As such, lay participants, compared to experts, perceive the consequences of diagnosis as more severe with respect to stopping work permanently, but do not differ in any other regard. This may reflect a pathologizing of a normal response, by viewing the consequences of medically explained and unexplained illnesses as similar (Boris, Ou & Singh, 2005; Wessely, 2005).

9.1.2.5 A hypothetical causal chain with respect to medically explained and unexplained illness Based on the above, a hypothetical chain of events may occur. Lay people consult an expert about anxiety or stress, experts are more likely to endorse work as a cause than lay people – but lay people still hold the belief that stress is caused by work. Lay people, compared to experts, are more likely to view stopping work as a consequence of being stressed. This may lead to a negotiated sickness absence. This reasoning is post-hoc and inferred from the pattern of findings, but is intuitively plausible. Only by studying in more detail expert and lay causal models in naturalistic settings (e.g., consultations: both hypothetical and real) or conducting experimental studies can these links be explored.

9.2 RECOMMENDATIONS – PRACTICAL IMPLICATIONS

The following is recommended for experts to consider when advising the lay public either directly or via health promotion messages.

9.2.1 The illness representations dimensions and cognitive structural models should be used as interactive educational tools. There is evidence that visual representations aid lay people’s understanding of side effects and risks in medicine (Edwards, Elwyn & Mulley, 2002). Although not directly tested here, one possible practical recommendation would be to explore lay and expert illness representation and use the resultant maps and descriptions to aid the consultation process. This may help the expert to explain their reasons for specified treatments and relate these to the individual own perceptions. The use of such an approach, 77 however, would require a full validation study, but the identified differences in this report suggest that this may be a fruitful line of enquiry.

9.2.2 Examine why lay people perceive stress as having more work related consequences than experts. Lay people were more likely to endorse stopping work, compared to experts, as a consequence of all the illnesses. While this was not the most strongly endorsed consequence, it was the only one where expert and lay participants differed. When discussing possible treatments and potential sickness absence for these illnesses, expert may wish to explore why lay people hold this view more strongly than they do and in so doing negotiate a better understanding.

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81 APPENDICES

82 APPENDIX 1 METHODS FOR DEVELOPING LAY MODELS

Questionnaires Using the existing measures as a generic template: The 4 questionnaires developed here can be used as generic templates and the focus of the disease can change. That is, the questions about causes, consequences, time line etc can remain the same – as can the sources of information. Only the name of the disease needs to be changed. The questionnaires that can be adapted can be found on pages 105-125 and 134.

However, we recommend that the following steps are adopted to enhance the validity of this process.

1. Pilot work: Pilot the illness (consult the literature and experts) a. Any new illness that is studied should be one that is easily understood by both lay and expert groups. For example, whereas most people will have heard of a heart attack less will be familiar with Carpal Tunnel Syndrome. If lay people have not head of the illness then they will be unable to answer the questionnaire meaningfully. b. Identify any extra pertinent symptoms and causes that can be added to the generic templates. 2. Additional items: Add any additional causes and symptoms. a. Pilot these on about 50 participants to check item distributions and remove items with ceiling or floor effects. b. Check the reliability of the scales (Cronbach’s alpha). 3. Administer questionnaire 4. Scoring: The symptoms, causes and sources of information can be treated as individual items. The scoring of the illness-representations items for time line, etc. can be found in Appendix 5.

Cognitive Maps The cognitive mapping procedures can also be used and adapted to any illness. 1. Develop putative causes via expert and lay interviews. a. This will involve consultation with expert and lay groups – as well as consulting the relevant literature. It is recommended that the number of causes used is kept to a manageable size. In the studies we report here we used 9 and found this to be manageable. Too many causes may lead to overly complex maps or ones that people find difficult to develop. b. Make sure that the causes can be expressed simply in terms of key words or phrases that are easily understood by both lay and expert groups. Do not use technical words or jargon. 2. Follow procedure can be used for doing a mapping study – see also chapter 2. a. Adapt the instructions as detailed on pages 126-130. b. On a sheet of paper place the illness centrally. c. Ask participants to arrange the causes on the paper such that they can also examine inter-relationships between causes. Allow them also to re-arrange the causes or the position of the illness so as they can achieve the best representation. d. Explain about drawing arrows to show the direction of the cause. e. Let people also have bi-directional arrows. f. Tell people to assign a value on a percentage scale to indicate the strength of the causal link and then to state whether it makes the illness worse or better. Make sure that you tell participants that causes can have positive/helpful as well as negative/detrimental effects.

83 g. Allow people to go back and change the strength, direction or position of any cause as they progress through the procedure. h. Allow people to review the process at the end and decide if they are happy with it. i. Take a photograph of the map for future reference and analysis.

84 APPENDIX 2 METHODS FOR DEVELOPING EDUCATIONAL MATERIALS

Below is a visual representation of the differences between experts and lay participants with respect to stress

EXPERTS LAY

CAUSES - CAUSES - Work Diet

DEFINITION – DEFINITION – Coherence Chronic Personal Control Cyclical Stress Serious

WORK EFFECTS – WORK EFFECTS – None Retire

SYMPTOMS – Depression Reduced mobility

SOURCES OF SOURCES OF INFORMATION – INFORMATION – Family/Friends HSE GP

85 From the analyses reported in this report it is possible to develop a visual representation of the differences between expert and lay participants. This can then be used as a point of departure during education and training sessions. Thus, using the techniques described in this report and detail in the appendices, measure of illness representations for any illness can be derived by changing the wording appropriately. The SCM procedures can be used if you are dealing with smaller sample sizes and the actual maps themselves used.

The use of visual representation is recommended as there is a growing body of research data in the area of risk perception indicating that visual representations aid understanding.

Advice on using cognitive maps

Develop the maps A simple way to use these in practice with individuals would be to ask them to arrange a number of causes (derived from the literature and practice) on a piece of paper in relation to the disease and then to ask them to draw arrows indicating how strong they see the relationship to be - as well as looking at the relationship between causes. The expert (practitioner) could have developed their model earlier. More detail on this process is provided in chapter 2, appendix 1 and from pages 126-133.

Questions that can be asked when the maps are completed From the comments by expert and lay participants the following issues could be discussed in any doctor-patient interaction.

(1) Highlight the similarities between models

(2) Highlight any gaps in knowledge to the patient

(3) Highlight important factors and say why they are important

(4) Highlight the fact that causal factors may interact with each other and that it is not so simple that each cause is an individual predictor

(5) Models could be developed further to start to discuss types of treatments and consequences of the illness

Need for Evaluation & Use in Practice As stated in the main text, the use of such cognitive mapping procedures in practice has not been evaluated and further work is needed to see if in fact it is (1) an easy-to-use technique that (2) aids patient (and expert) understanding – so each learns about the others perspective – and (3) promotes compliance with treatments. Therefore, the above only serves as a set of guidelines that may be useful for those interested in using this technique. A definitive set of guidelines on use in practice can only be given after further evaluative work. As such, it is recommended that anyone using this technique maintains evaluative monitoring of patient reactions and outcomes and adjusts their use accordingly.

86 APPENDIX 3 METHODS FOR DEVELOPING KNOWLEDGE QUESTIONS

The following is a brief description of the steps required to develop knowledge questions for a specific illness.

1. Select items by consulting text books and/or experts in the area. a. These items should be of a generic nature. Items that are highly specific about a disease process may be too difficult if the purpose is to explore knowledge in general lay populations. 2. Items need to be not too difficult or too easy to avoid ceiling and floor effects. a. Some small piloting with a group of lay (N = 10) and expert (N = 10) participants will help to explore this. Specifically, items should be answered and distributions of correct and incorrect responses examined to ensure that most people (80%+) are not getting all the items correct or incorrect.

3. Multiple choice options. a. Make sure all alternatives on the multiple choice answers are plausible – so that people cannot get the answer correct just through a process or elimination. b. It is recommended to have 4 options in the multiple choice (1 correct and 3 incorrect) c. Make sure only one of the alternatives is the correct answer.

4. Make sure to have an index of confidence. a. Ask participants to indicate the extent to which they are confident that they have got the answer correct (1 = totally unconfident to 4 = completely confident). b. A confidence estimate should follow each multiple-choice question.

87 APPENDIX 4 MATERIALS USED IN ALL STUDIES

Pilot Study Questionnaire

Interview Study Consent form Interview schedule Interview schedule illness fact sheets: Lung Cancer Multiple Sclerosis Carpal Tunnel Syndrome Asbestosis Tetanus Hernia Symptom checklist – incidence of reporting: Stress Multiple Sclerosis Lung Cancer Coding Framework

National Survey Study Surveys: Lung Cancer Asthma Stress Multiple Sclerosis Information Sheets: Asthma Lung Cancer Stress Multiple Sclerosis Cover Letters: Stress Asthma Multiple Sclerosis Lung Cancer

Cognitive Mapping Study Introduction sheets: Multiple Sclerosis Lung cancer Stress Asthma Consent Form Participant Information Sheet

88 PILOT STUDY

89 A) Age: ……….. B) Sex: M/F C) Occupation: ………….

Please consider the following list of diseases. To what extent do you believe they are caused by work? Please use the following scale:

0 10 Not at all Entirely

1) Lung Cancer 0 1 2 3 4 5 6 7 8 9 10

2) Tuberculosis 0 1 2 3 4 5 6 7 8 9 10

3) Hand/Arm Vibration 0 1 2 3 4 5 6 7 8 9 10

4) Shingles 0 1 2 3 4 5 6 7 8 9 10

5) Asthma 0 1 2 3 4 5 6 7 8 9 10

6) Tetanus 0 1 2 3 4 5 6 7 8 9 10

7) Chronic Fatigue Syndrome 0 1 2 3 4 5 6 7 8 9 10

8) Carpal Tunnel Syndrome 0 1 2 3 4 5 6 7 8 9 10

9) Asbestosis 0 1 2 3 4 5 6 7 8 9 10

10) Bronchitis 0 1 2 3 4 5 6 7 8 9 10

11) Hernia 0 1 2 3 4 5 6 7 8 9 10

12) Stress 0 1 2 3 4 5 6 7 8 9 10

13) Bone Cancer 0 1 2 3 4 5 6 7 8 9 10

14) Coronary Heart Disease 0 1 2 3 4 5 6 7 8 9 10

15) Dermatitis 0 1 2 3 4 5 6 7 8 9 10

16) Back Pain 0 1 2 3 4 5 6 7 8 9 10

17) Stomach Cancer 0 1 2 3 4 5 6 7 8 9 10

18) Measles 0 1 2 3 4 5 6 7 8 9 10

19) Multiple Sclerosis 0 1 2 3 4 5 6 7 8 9 10

20) Leukaemia 0 1 2 3 4 5 6 7 8 9 10

90 INTERVIEW STUDY

91 Health & Safety Executive / University of Nottingham

Participant Consent Form

We would be grateful if you would be willing to take part in our research. This research is part of a 2 Year project funded by the Health & Safety Executive, to consider the way people think about certain illnesses/diseases. Participation in this study is entirely voluntary, and you are under no obligation to take part. You are free to withdraw from the interview at any point, even if you have completed the consent form. Should you decide to take part in the interview, all information you provide will remain confidential and anonymous, and will be used for the purposes of this research only. If you are happy to continue with the study, then please sign below. Remember, signing this form does not mean you have to complete the study.

“I confirm that I have read the Participant Information Form, and that this study has been explained to me to my satisfaction. I understand that I am free to withdraw at any time. I agree to take part in this study.”

Signed Participant: Date:

Signed Researcher: Date:

We would like to tape record your interview. This is in order for us to transcribe your comments in full for the purposes of analysis. You are under no obligation to have your interview recorded. If you do agree to having your interview recorded you may ask to have the tape stopped at any time. If you do consent to having your interview recorded, please sign below.

“I confirm that I agree to have my interview tape recorded. I understand that am free to ask for the tape to be stopped at any time.”

Signed Participant: Date:

92 Interview Schedule

1. ID number:

2. Occupation:

3. Years Work Experience:

4. Have you ever suffered from an occupational disease or work-related disorder?

5. Do you know anyone who has ever suffered from an occupational disease or work-related disorder?

(Illness Name – schedule is identical for each illness)

1) What do you think are the symptoms of this disease?

2) What do you think are the causes of this disease?

3) How is this disease treated?

4) Over what period of time does the disease develop? Do you think the symptoms of this disease are always present or do they come and go?

5). Please estimate the number of new cases of this disease reported last year (2002/2003).

93 6) What percentage of these cases do you believe are caused by work?

7) Which industries do you think have particularly high prevalence of this disease?

94 Lung Cancer

1) What do you think are the symptoms of this disease?

Persistent cough Constant chest pain that increases with deep inhalation Coughing up blood Shortness of breath, wheezing, hoarseness Recurrent episodes of pneumonia or bronchitis Swelling of the face or neck Loss of appetite or weight loss Fatigue

2) What do you think are the causes of this disease?

Smoking – 87% Radon – radioactive gas found in soil – 15-22,000 deaths per year. – 12% Exposure to asbestos, uranium, arsenic, petroleum products

3) How is this disease treated?

Depends on type of cancer, size, location and extent of tumour. Chemotherapy for small cell lung cancer. Radiotherapy. Both = chemoradiation. Surgery for non-small cell lung cancer.

4) Over what period of time does the disease develop? Do you think the symptoms of this disease are always present or do they come and go?

Takes many years to develop. Changes in lung can begin immediately a person exposed to carcinogen, however. Abnormal cells may appear in lining of bronchi – continued exposure causes more abnormal cells, with potential to form tumour.

95 Multiple Sclerosis

1) What do you think are the symptoms of this disease?

Difficulty walking Numbness/pins and needles Pain on moving the eyes Dim or blurred vision Tremor Clumsiness Slurred speech Poor memory/feeling emotional/difficulty thinking logically Speech difficulties Inability to walk Painful muscle spasms Bladder and bowel problems Impotence Difficulty swallowing

2) What do you think are the causes of this disease?

Autoimmune disease – immune system reacting against healthy tissue. Not known – possibly viral infection Possibly genetic factors Possibly diet Possibly climate

3) How is this disease treated?

No cure Disease modifying drugs, eg: Steroids for optic neutritis Interferon beta Glatimar acetate Symptom controlling drugs Surgery

4) Over what period of time does the disease develop? Do you think the symptoms of this disease are always present or do they come and go?

Different types. Relapsing-remitting (90% of people) – symptoms flare up and then periods of remission. Primary progressive (10% of people) – no remission – disease gets progressively worse. Time period different for different people.

96 Carpal Tunnel Syndrome

1) What do you think are the symptoms of this disease?

Median nerve becomes pressed or squeezed at the wrist. Burning, tingling, itching numbness in the palm of the hand/fingers. Fingers feel useless and swollen – no swelling apparent. Tingling during the day or wake up in night. Unable to distinguish hot and cold. Muscles at base of thumb waste away. Decreased grip strength.

2) What do you think are the causes of this disease?

Combination of factors that increase pressure on the median nerve and tendons in the carpal tunnel. Congenital disposition. Trauma or injury to the wrist that cause swelling eg. sprain or fracture. Overactivity of the pituitary gland. Hypothyroidism. Rheumatoid arthritis. Mechanical problems in the wrist joint. Work stress. Repeated use of vibrating tools. Fluid retention during pregnancy. Development of cyst or tumour in the canal.

3) How is this disease treated?

Resting affected hand for at least 2 weeks. Avoiding activities that may worsen symptoms. Immobilising the wrist in splint to avoid further damage. Drugs (anti-inflammatories, diuretics) – reduce swelling. Corticosteroids – relieve pressure on median nerve. Vitamin supplements. Surgery - open release, endoscopic.

4) Over what period of time does the disease develop? Do you think the symptoms of this disease are always present or do they come and go?

Starts gradually, chronic or untreated cases symptoms worsen. Recurrence following treatment rare.

97 Asbestosis

1) What do you think are the symptoms of this disease?

Shortness of breath. Coughing. Dry crackling sound while inhaling. Chest pain.

2) What do you think are the causes of this disease?

Inhalation of asbestos fibres. Flakes of asbestos remain in the lungs and can not be broken down. Scarring and inflammation result. This prevents oxygen and carbon dioxide travelling between air sacs.

3) How is this disease treated?

Stop exposure to asbestos. Stop smoking.

4) Over what period of time does the disease develop? Do you think the symptoms of this disease are always present or do they come and go?

Slow progressive disease. No symptoms for 10 to 20 years. Shortness of breath worsens with time.

98 Tetanus

1) What do you think are the symptoms of this disease?

Painful muscular contractions, especially in jaw and neck. Abdominal rigidity. Generalised muscle spasms.

2) What do you think are the causes of this disease?

Toxin produced by bacteria. Common in the environment and can contaminate wounds, where toxin is produced which causes symptoms of tetanus.

3) How is this disease treated?

Give tetanus antitoxin.

4) Over what period of time does the disease develop? Do you think the symptoms of this disease are always present or do they come and go?

Acute. Symptoms start on average 10 days after exposure. Could be 1 day to several months though.

99 Hernia

1) What do you think are the symptoms of this disease?

Pain or discomfort and localised swelling somewhere on the surface of the abdomen. Damage or death of tissue in severe cases.

2) What do you think are the causes of this disease?

Opening or weakness in the muscular structure of the wall of the abdomen. Inherited factors e.g. muscle weakness Poor lifting. Poor abdominal posture. Weight control problems.

3) How is this disease treated?

Surgery – laparoscopic or laser. Pull defect together or bridge weakness with plastic/mesh.

100 STRESS 2 PAIN 0 SORE THROAT 1 NAUSEA 2 BREATHLESSNESS 1 WEIGHT LOSS 15 FATIGUE 0 STIFF JOINTS 0 SORE EYES 0 WHEEZINESS 11 HEADACHES 6 UPSET STOMACH SLEEP DISTURBANCES 15 0 DIZZINESS 0 LOSS OF STRENGTH

APPETITE DISRUPTION 7 ANXIETY 16 INABILITY TO COPE 5 SWEATING 5 PALPITATIONS 5 DEPRESSION 15 IRRITABLE 11

101 MULTIPLE SCLEROSIS 5 PAIN 0 SORE THROAT 0 NAUSEA 0 BREATHLESSNESS 0 WEIGHT LOSS 8 FATIGUE 0 STIFF JOINTS 0 SORE EYES 0 WHEEZINESS 1 HEADACHES 0 UPSET STOMACH SLEEP DISTURBANCES 0 2 DIZZINESS 8 LOSS OF STRENGTH

DIFFICULTY WALKING 17 BALANCE PROBLEMS 6 SPEECH PROBLEMS 5 COGNITIVE PROBLEMS 3 PINS/NEEDLES 5 NUMBNESS 6 VISUAL DISTURBANCE 11

102 LUNG CANCER 18 PAIN 0 SORE THROAT 0 NAUSEA 30 BREATHLESSNESS 7 WEIGHT LOSS 7 FATIGUE 0 STIFF JOINTS 0 SORE EYES 1 WHEEZINESS 0 HEADACHES 0 UPSET STOMACH SLEEP DISTURBANCES 0 0 DIZZINESS 4 LOSS OF STRENGTH

COUGH 27 MALAISE 2 LOSS OF APPETITE 2

103 TREATMENTS

ALTERNATIVE EXERCISE SURGERY REST DRUGS LIFESTYLE THERAPIES

TIMELINE SYMPTOMS

DEVELOPMENT PRESENCE OF SYMPTOMS

PHYSICAL BEHAVIOURAL PSYCHOLOGICAL QUICK GRADUAL VARIES ALWAYS FLUCTUATE PRESENT

BY TYPE BY PERSON CAUSES

ENVIRONMENTAL LIFESTYLE BIOLOGICAL PERSONALITY

WORK HABITS GENETICS INFECTION NATIONAL SURVEY STUDY

105 University of Nottingham National Lung Cancer Survey

1. Listed below are a number of symptoms. Please indicate on the scale below whether you think that a person with lung cancer would, on average, experience these symptoms. Please circle a number from 0 5, where: 0 = ‘not at all’ to 5 = ‘would experience these symptoms severely’. ANXIETY 0 1 2 3 4 5 COUGH 0 1 2 3 4 5 DEPRESSION 0 1 2 3 4 5 DECREASED MOBILITY 0 1 2 3 4 5 BREATHLESSNESS 0 1 2 3 4 5 FATIGUE 0 1 2 3 4 5 PAIN 0 1 2 3 4 5 VISUAL DISTURBANCE 0 1 2 3 4 5 HEADACHES 0 1 2 3 4 5 SLEEP DISTURBANCES 0 1 2 3 4 5

2. We are interested in what you think may cause lung cancer. Below is a list of possible causes of lung cancer. Please indicate how much you think that each causes lung cancer by circling a number from 1 5, where: 1 = ‘definitely not a cause’ to 5 = ‘definitely a cause’ POSSIBLE CAUSES

Hereditary – it runs in the family 1 2 3 4 5 A germ or virus 1 2 3 4 5 Diet or eating habits 1 2 3 4 5 Chance or bad luck 1 2 3 4 5 Poor medical care in the past 1 2 3 4 5 Pollution in the environment 1 2 3 4 5 Touching substances at work e.g. chemicals, metals 1 2 3 4 5 Breathing in substances at work e.g. dust 1 2 3 4 5 A person’s behaviour 1 2 3 4 5 A person’s mental attitude e.g. thinking about life negatively 1 2 3 4 5 Family problems or worries 1 2 3 4 5 Overwork 1 2 3 4 5 A person’s emotional state e.g. feeling down/lonely/anxious 1 2 3 4 5 Ageing 1 2 3 4 5 Alcohol 1 2 3 4 5 Smoking 1 2 3 4 5 Accident or injury 1 2 3 4 5 A person’s personality 1 2 3 4 5 Altered immunity 1 2 3 4 5 Lack of control at work 1 2 3 4 5 Lack of training at work 1 2 3 4 5 Pressure at work 1 2 3 4 5 Poor management at work 1 2 3 4 5 Poor support at work 1 2 3 4 5

106 3. Please indicate how much you agree or disagree with the following statements about lung cancer by ticking the appropriate box.

VIEWS ABOUT LUNG CANCER STRONLGY DISAGREE DISAGREE NEUTRAL AGREE STRONGLY AGREE Lung cancer is likely to be permanent rather than temporary The symptoms of lung cancer can be prevented by treatment Nothing a person does affects the severity of their lung cancer symptoms The symptoms of lung cancer change a great deal from day to day Having lung cancer would have maj or consequences on a person’s life Lung cancer causes difficulties for those who are close to the sufferer The symptoms of lung cancer come and go in cycles A person’s actions would have no effect on the severity of their lung cancer symptoms Treatment can control the symptoms of lung cancer Lung cancer lasts for a long time Having lung cancer would make a person feel anxious Having lung cancer would make a person feel angry I don’t understand much about lung cancer A person with lung cancer would have to stop their work permanently Having lung cancer would cause a person to take days off work A person with lung cancer should tell their employer about their illness An employer should protect people from anything at work that may worsen lung cancer symptoms People with lung cancer should be advised not to do certain jobs

4. How trustworthy do you think the following sources of information would be in providing you with information about lung cancer? Please circle your response using the scale of 1-7 below, where: 1 = ‘not at all trustworthy’ to 7 = ‘extremely trustworthy’. GP 1 2 3 4 5 6 7 Internet 1 2 3 4 5 6 7 Health and Safety Executive 1 2 3 4 5 6 7 Employer 1 2 3 4 5 6 7 Friends/family 1 2 3 4 5 6 7 Occupational health professionals 1 2 3 4 5 6 7 Newspapers/magazines 1 2 3 4 5 6 7 Television/radio 1 2 3 4 5 6 7 107 5. Please answer the following questions by circling the answer that you believe to be correct. After each question, please state how confident you are that the answer is correct by circling a number where: 1 = not at all confident 2 = fairly unconfident 3 = fairly confident and 4 = very confident

1. The average lung capacity of a healthy adult is: b) 1 litre b) 2 litres c) 5 litres d) 10 litres How confident are you that this answer is correct? 1 2 3 4

2. What is the average number of breaths per minute of a healthy adult? b) 5- 10 breaths b) 15-20 breaths c) 25-30 breaths d) 35-40 breaths How confident are you that this answer is correct? 1 2 3 4

3. For a healthy adult, what is the average range for resting pulse rate (beats per minute)? a) 20-60 bpm b) 40-80 bpm c) 60-100 bpm d) 80-110 bpm How confident are you that this answer is correct? 1 2 3 4

Please complete the following information: Age: ______Occupation:______(Please circle your answers) Sex: MALE FEMALE Have you ever suffered from any occupational disease? YES NO Do you know anyone who has ever suffered from any occupational disease? YES NO Do you suffer from lung cancer? YES NO Do you know anyone who has ever suffered from lung cancer? YES NO

If you have any further comments, please add them here:

Thank you for your time 108 University of Nottingham National Asthma Survey

1. Listed below are a number of symptoms. Please indicate on the scale below whether you think that a person with asthma would, on average, experience these symptoms. Please circle a number from 0-5, where: 0 = ‘not at all’ to 5 = ‘would experience these symptoms severely’. ANXIETY 0 1 2 3 4 5 COUGH 0 1 2 3 4 5 DEPRESSION 0 1 2 3 4 5 DECREASED MOBILITY 0 1 2 3 4 5 BREATHLESSNESS 0 1 2 3 4 5 FATIGUE 0 1 2 3 4 5 PAIN 0 1 2 3 4 5 VISUAL DISTURBANCE 0 1 2 3 4 5 HEADACHES 0 1 2 3 4 5 SLEEP DISTURBANCES 0 1 2 3 4 5

2. We are interested in what you think may cause asthma. Below is a list of possible causes of asthma. Please indicate how much you think that each causes asthma by circling a number from 1-5, where: 1 = ‘definitely not a cause’ to 5 = ‘definitely a cause’ POSSIBLE CAUSES

Hereditary – it runs in the family 1 2 3 4 5 A germ or virus 1 2 3 4 5 Diet or eating habits 1 2 3 4 5 Chance or bad luck 1 2 3 4 5 Poor medical care in the past 1 2 3 4 5 Pollution in the environment 1 2 3 4 5 Touching substances at work e.g. chemicals, metals 1 2 3 4 5 Breathing in substances at work e.g. dust 1 2 3 4 5 A person’s behaviour 1 2 3 4 5 A person’s mental attitude e.g. thinking about life negatively 1 2 3 4 5 Family problems or worries 1 2 3 4 5 Overwork 1 2 3 4 5 A person’s emotional state e.g. feeling down/lonely/anxious 1 2 3 4 5 Ageing 1 2 3 4 5 Alcohol 1 2 3 4 5 Smoking 1 2 3 4 5 Accident or injury 1 2 3 4 5 A person’s personality 1 2 3 4 5 Altered immunity 1 2 3 4 5 Lack of control at work 1 2 3 4 5 Lack of training at work 1 2 3 4 5 Pressure at work 1 2 3 4 5 Poor management at work 1 2 3 4 5 Poor support at work 1 2 3 4 5

109 3. Please indicate how much you agree or disagree with the following statements about asthma by ticking the appropriate box.

VIEWS ABOUT ASTHMA STRONLGY DISAGREE DISAGREE NEUTRAL AGREE STRONGLY AGREE Asthma is likely to be permanent rather than temporary The symptoms of asthma can be prevented by treatment Nothing a person does affects the severity of their asthma symptoms The symptoms of asthma change a great deal from day to day Having asthma would have maj or consequences on a person’s life Asthma causes difficulties for those who are close to the sufferer The symptoms of asthma come and go in cycles A person’s actions would have no effect on the severity of their asthma symptoms Treatment can control the symptoms of asthma Asthma lasts for a long time Having asthma would make a person feel anxious Having asthma would make a person feel angry I don’t understand much about asthma A person with asthma would have to stop their work permanently Having asthma would cause a person to take days off work A person with asthma should tell their employer about their illness An employer should protect people from anything at work that may worsen asthma symptoms People with asthma should be advised not to do certain jobs

4. How trustworthy do you think the following sources of information would be in providing you with information about asthma? Please circle your response using the scale of 1-7 below, where: 1 = ‘not at all trustworthy’ to 7 = ‘extremely trustworthy’. GP 1 2 3 4 5 6 7 Internet 1 2 3 4 5 6 7 Health and Safety Executive 1 2 3 4 5 6 7 Employer 1 2 3 4 5 6 7 Friends/family 1 2 3 4 5 6 7 Occupational health professionals 1 2 3 4 5 6 7 Newspapers/magazines 1 2 3 4 5 6 7 Television/radio 1 2 3 4 5 6 7

110 5. Please answer the following questions by circling the answer that you believe to be correct. After each question, please state how confident you are that the answer is correct by circling a number where: 1 = not at all confident 2 = fairly unconfident 3 = fairly confident and 4 = very confident

1. The average lung capacity of a healthy adult is: c) 1 litre b) 2 litres c) 5 litres d) 10 litres How confident are you that this answer is correct? 1 2 3 4

2. What is the average number of breaths per minute of a healthy adult? c) 5- 10 breaths b) 15-20 breaths c) 25-30 breaths d) 35-40 breaths How confident are you that this answer is correct? 1 2 3 4

3. For a healthy adult, what is the average range for resting pulse rate (beats per minute)? a) 20-60 bpm b) 40-80 bpm c) 60-100 bpm d) 80-110 bpm How confident are you that this answer is correct? 1 2 3 4

Please complete the following information: Age: ______Occupation: ______(Please circle your answers) Sex: MALE FEMALE Have you ever suffered from any occupational disease? YES NO Do you know anyone who has ever suffered from any occupational disease? YES NO Have you ever suffered from asthma? YES NO Do you know anyone who has ever suffered from asthma? YES NO

If you have any further comments, please add them here:

Thank you for your time 111 University of Nottingham National Stress Survey

1. Listed below are a number of symptoms. Please indicate on the scale below whether you think that a person with stress would, on average, experience these symptoms. Please circle a number from 0-5, where: 0 = ‘not at all’ to 5 = ‘would experience these symptoms severely’. ANXIETY 0 1 2 3 4 5 COUGH 0 1 2 3 4 5 DEPRESSION 0 1 2 3 4 5 DECREASED MOBILITY 0 1 2 3 4 5 BREATHLESSNESS 0 1 2 3 4 5 FATIGUE 0 1 2 3 4 5 PAIN 0 1 2 3 4 5 VISUAL DISTURBANCE 0 1 2 3 4 5 HEADACHES 0 1 2 3 4 5 SLEEP DISTURBANCES 0 1 2 3 4 5

2. We are interested in what you think may cause stress. Below is a list of possible causes of stress. Please indicate how much you think that each causes stress by circling a number from 1-5, where: 1 = ‘definitely not a cause’ to 5 = ‘definitely a cause’ POSSIBLE CAUSES

Hereditary – it runs in the family 1 2 3 4 5 A germ or virus 1 2 3 4 5 Diet or eating habits 1 2 3 4 5 Chance or bad luck 1 2 3 4 5 Poor medical care in the past 1 2 3 4 5 Pollution in the environment 1 2 3 4 5 Touching substances at work e.g. chemicals, metals 1 2 3 4 5 Breathing in substances at work e.g. dust 1 2 3 4 5 A person’s behaviour 1 2 3 4 5 A person’s mental attitude e.g. thinking about life negatively 1 2 3 4 5 Family problems or worries 1 2 3 4 5 Overwork 1 2 3 4 5 A person’s emotional state e.g. feeling down/lonely/anxious 1 2 3 4 5 Ageing 1 2 3 4 5 Alcohol 1 2 3 4 5 Smoking 1 2 3 4 5 Accident or injury 1 2 3 4 5 A person’s personality 1 2 3 4 5 Altered immunity 1 2 3 4 5 Lack of control at work 1 2 3 4 5 Lack of training at work 1 2 3 4 5 Pressure at work 1 2 3 4 5 Poor management at work 1 2 3 4 5 Poor support at work 1 2 3 4 5

112 3. Please indicate how much you agree or disagree with the following statements about stress by ticking the appropriate box.

VIEWS ABOUT STRESS STRONLGY DISAGREE DISAGREE NEUTRAL AGREE STRONGLY AGREE Stress is likely to be permanent rather than temporary The symptoms of stress can be prevented by treatment Nothing a person does affects the severity of their stress symptoms The symptoms of stress change a great deal from day to day Having stress would have major consequences on a person’s life Stress causes difficulties for those who are close to the sufferer The symptoms of stress come and go in cycles A person’s actions would have no effect on the severity of their stress symptoms Treatment can control the symptoms of stress Stress lasts for a long time Having stress would make a person feel anxious Having stress would make a person feel angry I don’t understand much about stress A person with stress would have to stop their work permanently Having stress would cause a person to take days off work A person with stress should tell their employer about their illness An employer should protect people from anything at work that may worsen the symptoms of stress People with stress should be advised not to do certain jobs

4. How trustworthy do you think the following sources of information would be in providing you with information about stress? Please circle your response using the scale of 1-7 below, where:

1 = ‘not at all trustworthy’ to 7 = ‘extremely trustworthy’. GP 1 2 3 4 5 6 7 Internet 1 2 3 4 5 6 7 Health and Safety Executive 1 2 3 4 5 6 7 Employer 1 2 3 4 5 6 7 Friends/family 1 2 3 4 5 6 7 Occupational health professionals 1 2 3 4 5 6 7 Newspapers/magazines 1 2 3 4 5 6 7 Television/radio 1 2 3 4 5 6 7

113 5. Please answer the following questions by circling the answer that you believe to be correct. After each question, please state how confident you are that the answer is correct by circling a number where: 1 = not at all confident 2 = fairly unconfident 3 = fairly confident and 4 = very confident

1. When a person is under excessive stress, the body can produce a chemical called : b) adrenalin b) progesterone c) sodium d) chlorine How confident are you that this answer is correct? 1 2 3 4

2. Which illness is stress most likely to cause? a) eczema b) heart disease c) asthma d) appendicitis How confident are you that this answer is correct? 1 2 3 4

3. For a healthy adult, what is the average range for resting pulse rate (beats per minute)? a) 20-60 bpm b) 40-80 bpm c) 60-100 bpm d) 80-110 bpm How confident are you that this answer is correct? 1 2 3 4

Please complete the following information: Age: ______Occupation: ______(Please circle your answers) Sex: MALE FEMALE Have you ever suffered from any occupational disease? YES NO Do you know anyone who has ever suffered from any occupational disease? YES NO Have you ever suffered from stress? YES NO (If ‘YES’, did you take time off work? YES NO) Do you know anyone who has ever suffered from stress? YES NO

If you have any further comments, please add them here:

Thank you for your time 114 University of Nottingham National Multiple Sclerosis Survey

1. Listed below are a number of symptoms. Please indicate on the scale below whether you think that a person with Multiple Sclerosis would, on average, experience these symptoms. Please circle a number from 0-5, where: 0 = ‘not at all’ to 5 = ‘would experience these symptoms severely’. ANXIETY 0 1 2 3 4 5 COUGH 0 1 2 3 4 5 DEPRESSION 0 1 2 3 4 5 DECREASED MOBILITY 0 1 2 3 4 5 BREATHLESSNESS 0 1 2 3 4 5 FATIGUE 0 1 2 3 4 5 PAIN 0 1 2 3 4 5 VISUAL DISTURBANCE 0 1 2 3 4 5 HEADACHES 0 1 2 3 4 5 SLEEP DISTURBANCES 0 1 2 3 4 5

2. We are interested in what you think may cause Multiple Sclerosis. Below is a list of possible causes of Multiple Sclerosis. Please indicate how much you think that each causes Multiple Sclerosis by circling a number from 1-5, where: 1 = ‘definitely not a cause’ to 5 = ‘definitely a cause’ POSSIBLE CAUSES

Hereditary – it runs in the family 1 2 3 4 5 A germ or virus 1 2 3 4 5 Diet or eating habits 1 2 3 4 5 Chance or bad luck 1 2 3 4 5 Poor medical care in the past 1 2 3 4 5 Pollution in the environment 1 2 3 4 5 Touching substances at work e.g. chemicals, metals 1 2 3 4 5 Breathing in substances at work e.g. dust 1 2 3 4 5 A person’s behaviour 1 2 3 4 5 A person’s mental attitude e.g. thinking about life negatively 1 2 3 4 5 Family problems or worries 1 2 3 4 5 Overwork 1 2 3 4 5 A person’s emotional state e.g. feeling down/lonely/anxious 1 2 3 4 5 Ageing 1 2 3 4 5 Alcohol 1 2 3 4 5 Smoking 1 2 3 4 5 Accident or injury 1 2 3 4 5 A person’s personality 1 2 3 4 5 Altered immunity 1 2 3 4 5 Lack of control at work 1 2 3 4 5 Lack of training at work 1 2 3 4 5 Pressure at work 1 2 3 4 5 Poor management at work 1 2 3 4 5 Poor support at work 1 2 3 4 5

115 3. Please indicate how much you agree or disagree with the following statements about Multiple Sclerosis by ticking the appropriate box.

VIEWS ABOUT MULTIPLE SCLEROSIS STRONLGY DISAGREE DISAGREE NEUTRAL AGREE STRONGLY AGREE Multiple Sclerosis is likely to be permanent rather than temporary The symptoms of Multiple Sclerosis can be prevented by treatment Nothing a person does affects the severity of their Multiple Sclerosis symptoms The symptoms of Multiple Sclerosis change a great deal from day to day Having Multiple Sclerosis would have major consequences on a person’s life Multiple Sclerosis causes difficulties for those who are close to the sufferer The symptoms of Multiple Sclerosis come and go in cycles A person’s actions would have no effect on the severity of their Multiple Sclerosis symptoms Treatment can control the symptoms of Multiple Sclerosis Multiple Sclerosis lasts for a long time Having Multiple Sclerosis would make a person feel anxious Having Multiple Sclerosis would make a person feel angry I don’t understand much about Multiple Sclerosis A person with Multiple Sclerosis would have to stop their work permanently Having Multiple Sclerosis would cause a person to take days off work A person with Multiple Sclerosis should tell their employer about their illness An employer should protect people from anything at work that may worsen Multiple Sclerosis symptoms People with Multiple Sclerosis should be advised not to do certain jobs 4. How trustworthy do you think the following sources of information would be in providing you with information about Multiple Sclerosis? Please circle your response using the scale of 1-7 below, where: 1 = ‘not at all trustworthy’ to 7 = ‘extremely trustworthy’. GP 1 2 3 4 5 6 7 Internet 1 2 3 4 5 6 7 Health and Safety Executive 1 2 3 4 5 6 7 Employer 1 2 3 4 5 6 7 Friends/family 1 2 3 4 5 6 7 Occupational health professionals 1 2 3 4 5 6 7 Newspapers/magazines 1 2 3 4 5 6 7 Television/radio 1 2 3 4 5 6 7 116 5. Please answer the following questions by circling the answer that you believe to be correct. After each question, please state how confident you are that the answer is correct by circling a number where: 1 = not at all confident 2 = fairly unconfident 3 = fairly confident and 4 = very confident

1. The Central Nervous System is made up of the: a) liver and kidneys b) heart and lungs c) brain and spinal chord d) stomach and intestines How confident are you that this answer is correct? 1 2 3 4

2. The primary cells of the nervous system are called: b) synapses b) neurones c) platelets d) muscles How confident are you that this answer is correct? 1 2 3 4

3. For a healthy adult, what is the average range for resting pulse rate (beats per minute)? a) 20-60 bpm b) 40-80 bpm c) 60-100 bpm d) 80-110 bpm How confident are you that this answer is correct? 1 2 3 4

Please complete the following information: Age: ______Occupation: ______(Please circle your answers) Sex: MALE FEMALE Have you ever suffered from any occupational disease? YES NO Do you know anyone who has ever suffered from any occupational disease? YES NO Do you suffer from Multiple Sclerosis? YES NO Do you know anyone who has suffered from Multiple Sclerosis? YES NO

If you have any further comments, please add them here:

Thank you for your time

117 University of Nottingham National Asthma Survey Information Sheet

Thank you for taking the time to read about our study. If you have any queries about the study please contact one of the project team. Our details are below:

Joanna Leaviss 0115 9515325 [email protected]

Dr Pete Bibby 0115 9515329 [email protected]

Dr Claire Lawrence 0115 9515326 [email protected]

Professor Eamonn Ferguson 0115 9515327 [email protected]

You may have some questions or concerns about asthma. Unfortunately we are unable to provide any personal support about this. If you do have any concerns about your health we would advise you in the first instance to contact your GP.

In addition, please find below the contact details for organisations that can provide specific advice about asthma and a number of health related topics:

• For general health advice:

NHS Direct 0845 46 47 www.nhsdirect.nhs.uk

• For advice about asthma:

Asthma UK Adviceline Ask an asthma nurse specialist 08457 01 02 03 9am–5pm, Monday–Friday www.asthma.org.uk/adviceline Interpreting service from more than 100 languages Calls charged at local rates Registered charity number 802364

• For anyone seeking help or guidance, or wishing to discuss their problems in confidence:

The Samaritans 08457 90 90 90 www.samaritans.org.uk

118 University of Nottingham National Lung Cancer Survey Information Sheet

Thank you for taking the time to read about our study. If you have any queries about the study please contact one of the project team. Our details are below:

Joanna Leaviss 0115 9515325 [email protected]

Dr Pete Bibby 0115 9515329 [email protected]

Dr Claire Lawrence 0115 9515326 [email protected]

Professor Eamonn Ferguson 0115 9515327 [email protected]

You may have some questions or concerns about lung cancer. Unfortunately we are unable to provide any personal support about this. If you do have any concerns about your health we would advise you in the first instance to contact your GP.

In addition, please find below the contact details for organisations that can provide specific advice about lung cancer and a number of health related topics:

• For general health advice:

NHS Direct 0845 46 47 www.nhsdirect.nhs.uk

• For advice about lung cancer:

British Lung Foundation 08458 505020 www.lunguk.org

• For anyone seeking help or guidance, or wishing to discuss their problems in confidence:

The Samaritans 08457 90 90 90 www.samaritans.org.uk

119 University of Nottingham National Stress Survey Information Sheet

Thank you for taking the time to read about our study. If you have any queries about the study please contact one of the project team. Our details are below:

Joanna Leaviss 0115 9515325 [email protected]

Dr Pete Bibby 0115 9515329 [email protected]

Dr Claire Lawrence 0115 9515326 [email protected]

Professor Eamonn Ferguson 0115 9515327 [email protected]

You may have some questions or concerns about stress. Unfortunately we are unable to provide any personal support about this. If you do have any concerns about your health we would advise you in the first instance to contact your GP.

In addition, please find below the contact details for organisations that can provide specific advice about stress and a number of health related topics:

• For general health advice:

NHS Direct 0845 46 47 www.nhsdirect.nhs.uk

• For advice about stress:

Health and Safety Executive 08701 545 500 www.hse.gov.uk

• For anyone seeking help or guidance, or wishing to discuss their problems in confidence:

The Samaritans 08457 90 90 90 www.samaritans.org.uk

120 University of Nottingham National Multiple Sclerosis Survey Information Sheet

Thank you for taking the time to read about our study. If you have any queries about the study please contact one of the project team. Our details are below:

Joanna Leaviss 0115 9515325 [email protected]

Dr Pete Bibby 0115 9515329 [email protected]

Dr Claire Lawrence 0115 9515326 [email protected]

Professor Eamonn Ferguson 0115 9515327 [email protected]

You may have some questions or concerns about multiple sclerosis. Unfortunately we are unable to provide any personal support about this. If you do have any concerns about your health we would advise you in the first instance to contact your GP.

In addition, please find below the contact details for organisations that can provide specific advice about multiple sclerosis and a number of health related topics:

• For general health advice:

NHS Direct 0845 46 47 www.nhsdirect.nhs.uk

• For advice about Multiple Sclerosis:

Multiple Sclerosis Society 0808 800 8000 www.mssociety.org.uk

• For anyone seeking help or guidance, or wishing to discuss their problems in confidence:

The Samaritans 08457 90 90 90 www.samaritans.org.uk

121 April 2005 Dear University of Nottingham National Stress Survey

Researchers at the University of Nottingham are exploring the way in which people think about stress. The project is funded by the UK Health and Safety Executive (HSE), but is being carried out by independent researchers within the School of Psychology at the University of Nottingham. We are conducting a national survey to find out more about people’s thoughts about stress. We are interested in your thoughts about what causes stress, the symptoms that someone with stress has, and how it might be treated. Information collected from the survey will provide a better awareness of people’s beliefs about stress. You have been randomly selected to receive a copy of this survey, which has been mailed to you by an independent company on our behalf. You will not receive any more correspondence from us. Take some time to look over the survey and this letter. If you are happy to participate then please complete the survey, and return it to us in the prepaid envelope provided. Your responses will be used only for the purposes of this research. Please try to complete all the questions in the survey. However your survey is still useful to us even if you have missed out some questions or sections, so please complete what you can and return it to us. Although the survey was addressed to you, it can be completed by anyone in your household over the age of 18. This survey is voluntary and you do not have to complete it. Members of the research team have no information on who has been sent the surveys, and they contain no features that would identify you. Therefore, all responses are anonymous. You do not have to complete the survey once you have started or to return the survey once completed. If you would like any further information about the study, please do contact a member of the research team. Our details are listed overleaf. Please also contact us if you would like a large print or Braille version of this survey. If you have any general concerns about stress or your health in general, we have included a list of telephone numbers and websites of organisations that you may find useful. When you have completed the survey, please send it back to us in the pre-paid envelope provided within two weeks, or as soon as possible after that. Thank you in advance for your participation, Yours sincerely,

Joanna Leaviss Research Associate

122 April 2005 Dear

University of Nottingham National Asthma Survey

Researchers at the University of Nottingham are exploring the way in which people think about asthma. The project is funded by the UK Health and Safety Executive (HSE), but is being carried out by independent researchers within the School of Psychology at the University of Nottingham. We are conducting a national survey to find out more about people’s thoughts about asthma. We are interested in your thoughts about what causes asthma, the symptoms that someone with asthma has, and how it might be treated. Information collected from the survey will provide a better awareness of people’s beliefs about asthma. You have been randomly selected to receive a copy of this survey, which has been mailed to you by an independent company on our behalf. You will not receive any more correspondence from us. Take some time to look over the survey and this letter. If you are happy to participate then please complete the survey, and return it to us in the prepaid envelope provided. Your responses will be used only for the purposes of this research. Please try to complete all the questions in the survey. However your survey is still useful to us even if you have missed out some questions or sections, so please complete what you can and return it to us. Although the survey was addressed to you, it can be completed by anyone in your household over the age of 18. This survey is voluntary and you do not have to complete it. Members of the research team have no information on who has been sent the surveys, and they contain no features that would identify you. Therefore, all responses are anonymous. You do not have to complete the survey once you have started or to return the survey once completed. If you would like any further information about the study, please do contact a member of the research team. Our details are listed overleaf. Please also contact us if you would like a large print or Braille version of this survey. If you have any general concerns about asthma or your health in general, we have included a list of telephone numbers and websites of organisations that you may find useful. When you have completed the survey, please send it back to us in the pre-paid envelope provided within two weeks, or as soon as possible after that. Thank you in advance for your participation, Yours sincerely,

Joanna Leaviss Research Associate

123 April 2005 Dear Sir/Madam,

University of Nottingham National Multiple Sclerosis Survey

Researchers at the University of Nottingham are exploring the way in which people think about multiple sclerosis. The project is funded by the UK Health and Safety Executive (HSE), but is being carried out by independent researchers within the School of Psychology at the University of Nottingham. We are conducting a national survey to find out more about people’s thoughts about multiple sclerosis. We are interested in your thoughts about what causes multiple sclerosis, the symptoms that someone with multiple sclerosis has, and how it might be treated. Information collected from the survey will provide a better awareness of people’s beliefs about multiple sclerosis. You have been randomly selected to receive a copy of this survey, which has been mailed to you by an independent company on our behalf. You will not receive any more correspondence from us. Take some time to look over the survey and this letter. If you are happy to participate then please complete the survey, and return it to us in the prepaid envelope provided. Your responses will be used only for the purposes of this research. Please try to complete all the questions in the survey. However your survey is still useful to us even if you have missed out some questions or sections, so please complete what you can and return it to us. Although the survey was addressed to you, it can be completed by anyone in your household over the age of 18. This survey is voluntary and you do not have to complete it. Members of the research team have no information on who has been sent the surveys, and they contain no features that would identify you. Therefore, all responses are anonymous. You do not have to complete the survey once you have started or to return the survey once completed. If you would like any further information about the study, please do contact a member of the research team. Our details are listed overleaf. Please also contact us if you would like a large print or Braille version of this survey. If you have any general concerns about multiple sclerosis or your health in general, we have included a list of telephone numbers and websites of organisations that you may find useful. When you have completed the survey, please send it back to us in the pre-paid envelope provided within two weeks, or as soon as possible after that. Thank you in advance for your participation, Yours sincerely,

Joanna Leaviss Research Associate

124 April 2005 Dear University of Nottingham National Lung Cancer Survey

Researchers at the University of Nottingham are exploring the way in which people think about lung cancer. The project is funded by the UK Health and Safety Executive (HSE), but is being carried out by independent researchers within the School of Psychology at the University of Nottingham. We are conducting a national survey to find out more about people’s thoughts about lung cancer. We are interested in your thoughts about what causes lung cancer, the symptoms that someone with lung cancer has, and how it might be treated. Information collected from the survey will provide a better awareness of people’s beliefs about lung cancer. You have been randomly selected to receive a copy of this survey, which has been mailed to you by an independent company on our behalf. You will not receive any more correspondence from us. Take some time to look over the survey and this letter. If you are happy to participate then please complete the survey, and return it to us in the prepaid envelope provided. Your responses will be used only for the purposes of this research. Please try to complete all the questions in the survey. However your survey is still useful to us even if you have missed out some questions or sections, so please complete what you can and return it to us. Although the survey was addressed to you, it can be completed by anyone in your household over the age of 18. This survey is voluntary and you do not have to complete it. Members of the research team have no information on who has been sent the surveys, and they contain no features that would identify you. Therefore, all responses are anonymous. You do not have to complete the survey once you have started or to return the survey once completed. If you would like any further information about the study, please do contact a member of the research team. Our details are listed overleaf. Please also contact us if you would like a large print or Braille version of this survey. If you have any general concerns about lung cancer or your health in general, we have included a list of telephone numbers and websites of organisations that you may find useful. When you have completed the survey, please send it back to us in the pre-paid envelope provided within two weeks, or as soon as possible after that. Thank you in advance for your participation, Yours sincerely,

Joanna Leaviss Research Associate

125 COGNITIVE MAPPING STUDY

126 The following factors may be important in causing multiple sclerosis: genetics, medical history, a virus, climate, stress, diet/exercise, age, sex and ethnic background. We would like you to make up a diagram using the labels provided, of how you think these causes are linked to multiple sclerosis and to each other, using arrows to indicate the direction of the effect. We would also like you to rate the strength of the link on a scale of 1-100 and write the appropriate number onto the diagram. If you think that the factor has a negative effect (i.e. causes the illness or makes it worse) then place a minus sign (-) after the number. If you think that the factor has a positive or beneficial effect (i.e. can make the illness better or alleviate symptoms), then place a plus sign (+) after the number. If you do not think that a cause has an important effect leave it off your diagram. Only include those causes that you think are important.

127 The following factors may be important in causing lung cancer: genetics, smoking, diet/exercise, exposure to carcinogens, past medical history, air pollution, age, sex, ethnic background. We would like you to make up a diagram using the labels provided, of how you think these causes are linked to lung cancer and to each other, using arrows to indicate the direction of the effect. We would also like you to rate the strength of the link on a scale of 1 100 and write the appropriate number onto the diagram. If you think that the factor has a negative effect (i.e. causes the illness or makes it worse) then place a minus sign (-) after the number. If you think that the factor has a positive or beneficial effect (i.e. can make the illness better or alleviate symptoms), then place a plus sign (+) after the number. If you do not think that a cause has an important effect leave it off your diagram. Only include those causes that you think are important.

128 The following factors may be important in causing stress: personality, diet/exercise, social support/coping mechanisms, workload, domestic situation, job dissatisfaction, age, sex, ethnic background. We would like you to make up a diagram using the labels provided, of how you think these causes are linked to stress and to each other, using arrows to indicate the direction of the effect. We would also like you to rate the strength of the link on a scale of 1-100 and write the appropriate number onto the diagram. If you think that the factor has a negative effect (i.e. causes the illness or makes it worse) then place a minus sign (-) after the number. If you think that the factor has a positive or beneficial effect (i.e. can make the illness better or alleviate symptoms), then place a plus sign (+) after the number. If you do not think that a cause has an important effect leave it off your diagram. Only include those causes that you think are important.

129 The following factors may be important in causing asthma: genetics, irritants, diet/exercise, air pollution, past medical history, allergies, age, sex, ethnic background. We would like you to make up a diagram using the labels provided, of how you think these causes are linked to lung cancer and to each other, using arrows to indicate the direction of the effect. We would also like you to rate the strength of the link on a scale of 1-100 and write the appropriate number onto the diagram. If you think that the factor has a negative effect (i.e. causes the illness or makes it worse) then place a minus sign (-) after the number. If you think that the factor has a positive or beneficial effect (i.e. can make the illness better or alleviate symptoms), then place a plus sign (+) after the number. If you do not think that a cause has an important effect leave it off your diagram. Only include those causes that you think are important.

130 Health & Safety Executive / University of Nottingham

Participant Consent Form

We would be grateful if you would be willing to take part in our research. This research is part of a 2 Year project funded by the Health & Safety Executive, to consider the way people think about certain illnesses/diseases. Participation in this study is entirely voluntary, and you are under no obligation to take part. You are free to withdraw from the cognitive mapping exercise at any point, even if you have completed the consent form. Should you decide to take part in the exercise, all information you provide will remain confidential and anonymous, and will be used for the purposes of this research only. If you are happy to continue with the study, then please sign below. Remember, signing this form does not mean you have to complete the study.

“I confirm that I have read the Participant Information Form, and that this study has been explained to me to my satisfaction. I understand that I am free to withdraw at any time. I agree to take part in this study.”

Signed Participant: Date:

Signed Researcher: Date:

131 Health & Safety Executive / University of Nottingham Lay and Expert Perceptions of Illness – Cognitive Maps

Participant Information Sheet

Thank you for taking part in our research. This research is part of a 2 Year project funded by the Health & Safety Executive, to consider the way people think about certain illnesses/diseases. If you have any queries about the study please contact one of the project team. Our details are below:

Joanna Leaviss 0115 9515325 [email protected]

Dr Pete Bibby 0115 9515329 [email protected]

Dr Claire Lawrence 0115 9515326 [email protected]

Professor Eamonn Ferguson 0115 9515327 [email protected]

132 If you have any questions or concerns about any of the illnesses highlighted in this study, please find below the contact details for organisations that can provide illness- specific advice or general advice on a number of health related topics:

• For general health advice: NHS Direct 0845 46 47 www.nhsdirect.nhs.uk

• For advice about asthma:

Asthma UK Adviceline Ask an asthma nurse specialist 08457 01 02 03 9am–5pm, Monday–Friday www.asthma.org.uk/adviceline

• For advice about lung cancer: British Lung Foundation 08458 505020 www.lunguk.org

• For advice about Multiple Sclerosis: Multiple Sclerosis Society 0808 800 8000 www.mssociety.org.uk

• For anyone seeking help or guidance, or wishing to discuss their problems in confidence:

The Samaritans 08457 90 90 90 www.samaritans.org.uk

133 APPENDIX 5 CALCULATING ILLNESS REPRESENTATION SCORES FROM QUESTIONNAIRE MATERIALS

Most of the variables derived from the questionnaire materials are single-item measures, but 6 of the 7 (IPQ-R) illness representations are computed from multiple items in the questionnaire. This appendix describes the correspondence between items in the questionnaire and the 7 illness representation factors.

The table below shows each of the illness representation items in the questionnaire and the factor that they relate to:

Item Illness Representation 1. [Illness] is likely to be permanent rather than temporary Timeline-acute/chronic 2. The symptoms of [illness] can be prevented by treatment Treatment Control 3. Nothing a person does affects the severity of their [illness] Personal Control symptoms 4. The symptoms of [illness] change a great deal from day to Timeline-cyclical day 5. Having[ illness] would have major consequences on a Serious Consequences person’s life 6. [Illness] causes difficulties for those who are close to the Serious Consequences sufferer 7. The symptoms of [illness] come and go in cycles Timeline-cyclical 8. A person’s actions would have no effect on the severity of Personal Control their [illness] symptoms 9. Treatment can control the symptoms of [illness] Treatment Control 10. [Illness] lasts for a long time Timeline-acute/chronic 11. Having [illness] would make a person feel anxious Emotion Representations 12. Having [ illness] would make a person feel angry Emotion Representations 13. I don’t understand much about [illness] Illness Coherence

Scores for each illness representation factor are computed by adding together the appropriate item scores (e.g., scores on items 4 and 7 for Timeline-cyclical) and dividing the total by the number of items (all factors apart from Illness Coherence are represented by 2 items). Note that Personal Control items should be reverse-scored prior to this computation.

Published by the Health and Safety Executive 06/06 RR 469