Socioeconomic Determinants of Health Disparities by Race and Ethnicity: The Mediating Role of Social, Psychological and Behavioral Factors

Abstract

Socioeconomic status (SES) is inversely related to health status. Disparities in health status among races and ethnic groups are partly attributable to differences in SES, but the indirect pathways by which SES may influence health status are not widely studied. Using the Health and Retirement Study (HRS) data, this dissertation examined the pathways by which SES, via social, psychological, and behavioral factors predicted physical impairment and overnight hospitalization, and asked whether these indirect relationships differed by race/ethnicity. The HRS is a nationally representative multistage area probability sample administered biennially to respondents over the age of 51 and their spouses. Data collected between 2002 and 2010, covering five waves of the original HRS cohort born between the years 1931and 1941, were used. Two analysis approaches, Structural Equation Modeling (SEM) and Reconstructability Analysis (RA), were used. Adjustments for the complex survey design were made in the SEM analysis, whereas, data were matched for the RA method using propensity scores. Results of the SEM analyses supported most of the hypothesized indirect relationships between SES variables and physical impairment via social and psychological factors, but the indirect effect of SES on physical impairment via behavioral factors was weak. Multiple group analyses of path equality using nested chisquare tests indicated that the indirect effect of SES on physical impairment status did not vary by race/ethnicity. Social, psychological and behavioral factors were weakly related vi Over several years, I was mentored by some of the best and generous educators and I will always be grateful for their time. Thanks to Dr. Francis Wambalaba who introduced me to research methods at the United States International University-Nairobi, Kenya. Thanks to Dr. Paula Carder (PSU) and Dr. Ana Quiñones (OHSU-PSU) for their support, collaborative research and mentorship. Because of the opportunities you provided, I learned important new skills. This journey was not easy but it would have been nearly impossible without the constant support of friends, relatives and colleagues. Thanks are due to Dr. Moses Wambalaba and his family who graciously hosted me during the first week in the U.S. and introduced me to PSU the next day I arrived. Special thanks to my aunt Kibirti Zemam and her family for always being there for me and checking up on my progress and well-being. I also express my heartfelt gratitude to my cousin Elilta (Lily) Habtu and my friend Zeccharias Arey for their constant support over the years. Thanks to my friends and colleagues

The Effect of Electron Diffusion on the Instability of a Townsend Discharge

“…The physics of space charge driven transitions of a Townsend discharge to subnormal, normal and further to abnormal glow has drown considerable attention of the discharge investigating community (Refs. [4]- [10] and references therein). Numerous experimental, analytical and numerical investigations provide deep insight into amazing variety of spatio-temporal processes, which are responsible for such transitions.…”