Project Summary In 1980 Black male youths in Harlem, New York City were estimated to being less likely to survive to the age of 65 than male youths in Bangladesh. Mortality rates in 1980 were estimated to be roughly 6 times greater among Black Harlem men and women than White men and women in the same age groups. Research has shown that these profound disparities – often understood to the be result of social stress and other factors that produce earlier onset of disease, greater disease severity, and poorer quality healthcare to deal with morbidity – remain considerable. The COVID-19 pandemic has not only wiped away any forward progress in these disparities but has actually seemed to cause larger ethnoracial health disparities. Estimates show that COVID-19 will reduce US life expectancy in 2020 by a full year for Whites and the reductions for African Americans will be 3-4 times this. Additionally, this reduction in life expectancy will likely persist beyond 2020 because of continued COVID-19 mortality and long- term health, social, and economic impacts of the pandemic. Understanding minority health and health disparities has long been a core priority of the NIH. Among the key strategies for advancing the science of minority health and health disparities are: 1) comprehensively measuring how social stress, which affects health by causing dysregulation of the Hypothalamo- Pituitary-Adrenocortical axis (HPA axis), 2) rigorous methodological approaches that enable causal inference approaches (e.g. longitudinal analyses), and 3) improving patient-clinician relations and diagnostic procedures for equitable care across ethnoracial categories. Accordingly, this project considers two pathways through which skin tone may affect minority health: social stress and differential quality of healthcare related to algorithmic biases built into medical technology – pulse oximetry. Pulse oximetry, in particular, is especially critical during the age of COVID where overestimating the oxygen saturation of minorities may lead to them not receiving treatment even though they need medical intervention. The former pathway will be investigated through a longitudinal, nationally representative survey of African Americans (with sub-sample of Whites) with a host of measures of heretofore unexamined sources of social stress. The latter pathway will be investigated in collaboration with experts in optics who I will work with to assess algorithmic biases in pulse oximetry and, ultimately, design solutions to ensure that pulse oximetry works equally well across the skin color continuum.

Project Narrative Research on ethnoracial health disparities tends to compare between ethnoracial categories (e.g. Blacks and Whites) while ignoring heterogeneity in socioeconomic status and health within ethnoracial categories. Studies show, however, that there is considerable heterogeneity in socioeconomic status and health among African Americans – in fact, in some cases there is as much inequality in socioeconomic status, criminal justice outcomes, and health within the Black population along the skin tone continuum as there is between African Americans and Whites as a whole. This proposal details two parallel projects designed to examine this intraracial heterogeneity in health among African Americans along the skin tone continuum: 1) a novel, longitudinal, nationally representative survey of African Americans and 2) a cutting-edge project aimed at assessing and fixing skin tone-related algorithmic biases in pulse oximetry.