Title: Explaining the Black-White Depression Paradox
Description: According to large nationally-representative epidemiologic surveys, Black individuals in the U.S. experience a lesser or equal prevalence of DSM diagnosed major depression, relative to White individuals, despite experiencing greater exposure to major life stressors, a known cause of major depression. This finding, often referred to as the Black-White Depression Paradox, has been the subject of many studies; however, the drivers of the phenomenon remain unknown. The objective of this dissertation is to advance understanding of the explanatory mechanisms that produce the paradox, through critical examination of existing evidence and empirical assessment of untested hypotheses. This dissertation is divided into five chapters, the first of which is an introduction to the dissertation. The second chapter is a critical review of extant evidence for existing hypothesized explanatory mechanisms for the depression paradox. Chapters 3 and 4 are both empirical analyses using data from the National Epidemiologic Survey on Alcohol and Related Conditions-III.

Chapter 3 tests two possible causal structures for the relationships between race, life stressor exposure, and depression that would be consistent with observed racial patterns of depression, an effect modification causal structure that would suggest that the paradox is caused by racial patterns in life stressor coping, and an inconsistent mediation causal structure, which would suggest that the paradox is produced by Black individuals having a reduced baseline risk of depression, independent of their life stressor exposure. Chapter 4 subsequently assesses whether religiosity could produce the paradox by being an explanatory mechanism for the causal structure best supported in Chapter 3. The dissertation ends with Chapter 5, which summarizes the results of the dissertation, and situates the findings within the broader psychiatric epidemiologic literature. The critical review found that many hypothesized mechanisms had been posited, but none of the mechanisms that had been sufficiently empirically tested had robust, compelling evidence.

However, one hypothesized mechanism in particular, religiosity, has been posited frequently as a potential explanation for the paradox, has compelling indirect support, but has yet to be sufficiently empirically tested. Chapter 3 failed to find support for an effect modification causal structure for the relationships between race, life stressor exposure, and depression. However, the findings did support an inconsistent mediation causal structure, whereby the effect of Black race not mediated by life stressor exposure was protective of depression, and was stronger than the deleterious effect mediated by life stressor exposure. This finding suggests that the pathways to depression that are salient for the paradox are those operating independent of life stressor exposure. However, Chapter 4 failed to find support for religiosity operating as a mediating mechanism for this salient, life-stressor independent pathway. Results of these studies suggest the need to develop and empirically test novel hypothesized explanatory mechanisms for the paradox, specifically mechanisms that would explain a lower baseline risk of depression for Black individuals, independent of their life stressor exposure.