Inequities in Access to Five Types of Healthcare Services

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Inequities in Access to Five Types of Healthcare Services UNIVERSITY OF CALIFORNIA Los Angeles Rurality and Race: Inequities in Access to Five Types of Healthcare Services A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Public Health by Julia Thornton Caldwell 2015 © Copyright by Julia Thornton Caldwell 2015 ABSTRACT OF THE DISSERTATION Rurality and Race: Inequities in Access to Five Types of Healthcare Services by Julia Thornton Caldwell Doctor of Philosophy in Public Health University of California, Los Angeles, 2015 Professor Chandra L. Ford, Chair Background. Rurality may influence racial/ethnic disparities in access to healthcare. This study sought to: (1) compare and contrast measures used to assess rurality and urbanicity; (2) determine if racial/ethnic disparities in access to healthcare differ for rural vs. urban areas; and, (3) determine if residential segregation and access to healthcare differ for rural vs. urban areas. Sample. The sample was adult respondents to the 2005-2010 Medical Expenditure Panel Survey (MEPS), a nationally representative sample of U.S. households. Each aim had five samples; sample size ranged from 49,839 to 112,125. Measures. Aim 1 involved five measures used to identify rurality relative to urbanicity. Aim 2 and aim 3 involved five self-reported MEPS outcomes indicating whether respondents had (1) a usual source of healthcare, (2) unmet need for healthcare, (3) cholesterol screenings, (4) cervical cancer screenings, or (5) dental visits. The main explanatory factors, which were based on respondents’ residential location, were rurality and residential segregation, which were examined separately for blacks and Hispanics using the isolation index. Respondents’ residential areas were characterized by using geographic identifiers to link the MEPS data with ii census tract and county information available via the American Community Survey (2005-2010), the Area Health Resource File (2010), and five publically available rurality indicators. Analysis. The descriptive analysis explored variable characteristics and bivariate associations. The main analysis involved multi-level, random intercept logistic regression to estimate disparities in each access to healthcare outcome while controlling for confounders. Results. One outcome, unmet healthcare need, changed depending on the measure used to assess rurality. With respect to disparities, relatively more blacks than whites had preventive screenings in the fully adjusted models; this difference was smaller in rural than urban areas. Rural blacks and Hispanics had fewer screenings than urban ones did. Across rural and urban areas, blacks and Hispanics in segregated areas had lower levels of unmet need. Discussion. Unadjusted estimates suggest disadvantaged rates for certain measures of access to healthcare by rurality and segregation, while adjusted models attenuated some of these disparities. Conclusion. Place-based factors (rurality, segregation) and racial factors may jointly affect access to healthcare among diverse U.S. populations. iii The dissertation of Julia Thornton Caldwell is approved. Steven P. Wallace May-Choo Wang Lois M. Takahashi Xiao Chen Chandra L. Ford, Committee Chair University of California, Los Angeles 2015 iv To my family, who from an early age instilled in me the value of education. v TABLE OF CONTENTS CHAPTER 1. INTRODUCTION TO THE DISSERTATION ......................................................... 1 1.1 Purpose ............................................................................................................................... 1 1.2 Statement of Problem .......................................................................................................... 1 1.3 Specific Aims ....................................................................................................................... 2 1.4 Significance .......................................................................................................................... 3 1.5 Overview of Dissertation ...................................................................................................... 4 CHAPTER 2. LITERATURE REVIEW ........................................................................................ 5 2.1 Introduction .......................................................................................................................... 5 2.2 Access to Healthcare ........................................................................................................... 5 2.3 Access to Healthcare in Rural and Urban Areas .................................................................. 8 2.4 Racial and Ethnic Disparities in Access to Healthcare .........................................................17 2.5 Poverty ................................................................................................................................27 2.6 Healthcare System ..............................................................................................................28 2.7 Summary ............................................................................................................................31 CHAPTER 3. THEORETICAL FRAMEWORK & RESEARCH AIMS .........................................32 3.1 Introduction .........................................................................................................................32 3.2 Andersen’s Behavioral Model of Health Services Use .........................................................32 3.3 Theory of Fundamental Causes ..........................................................................................34 3.4 Conceptual Model ...............................................................................................................35 3.5 Research Aims and Hypotheses .........................................................................................41 CHAPTER 4. METHODOLOGY ................................................................................................50 4.1 Introduction .........................................................................................................................50 4.2 Data Sources ......................................................................................................................50 4.3 Creation of Data File, Project Management, Institutional Review Board and Human Subjects Protections ................................................................................................................................58 4.4 Study Measures ..................................................................................................................60 4.4.1 Dependent Variables ........................................................................................................60 4.4.2 Contextual Level Variables ...............................................................................................63 4.4.3 Compositional Level Variables .........................................................................................72 4.4.4 Other Control Variables ....................................................................................................77 4.5 Analytic Samples.................................................................................................................79 4.5.1 Missing Data ....................................................................................................................79 4.5.2 Aim 1 Analytic Samples ....................................................................................................80 4.5.3 Aim 2 Analytic Samples ....................................................................................................81 4.5.4 Aim 3 Analytic Samples ....................................................................................................82 4.6 Sample Weights & Variance Structure ................................................................................83 4.7 Analytic Plan .......................................................................................................................85 4.7.1 Analysis of Aim 1 ..............................................................................................................86 4.7.2 Analysis of Aim 2 ..............................................................................................................86 4.7.3 Analysis of Aim 3 ..............................................................................................................91 CHAPTER 5. RESULTS: AIM 1 ................................................................................................94 5.1 Introduction .........................................................................................................................94 5.2 Descriptive Analyses ...........................................................................................................95 5.3 Objective 1 ..........................................................................................................................95 5.4 Objective 2 ..........................................................................................................................97 vi 5.5 Objective 3 ..........................................................................................................................98 5.6 Summary of Key Findings ................................................................................................. 100 CHAPTER 6. RESULTS: AIM 2 .............................................................................................
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