Shervin Assari

Background: Blacks' diminished return is defined as smaller protective effects of socioeconomic status (SES) on health of African Americans compared to Whites. Using a nationally representative sample, the current study aimed to examine if the protective effect of income on chronic medical conditions (CMC) differs for African Americans compared to Whites. Methods: With a cross-sectional design, the National Survey of American Life (NSAL), 2003, included 3570 non-Hispanic African Americans and 891 non-Hispanic Whites. The dependent variable was CMC, treated as a continuous measure. The independent variable was income. Race was the focal moderator. Age, education, and marital status were covariates. Linear regressions were used to test if the protective effect of income against CMC varies by race. Results: High income was associated with a lower number of CMC in the pooled sample. We found a significant interaction between race and income, suggesting that income has a smaller protective effect against CMC for African Americans than it does for Whites. Conclusion: Blacks' diminished return also holds for the effects of income on CMC. Blacks' diminished return is a contributing mechanism to the racial disparities in health in the United States that is often overlooked. More research is needed on the role of diminished health return of SES resources among other minority groups.