Project summary/abstract. Candidate. Christopher Chesley, MD, MSCE, is a pulmonary and critical care physician and health equity researcher who is committed to eliminating disparities related to acute respiratory failure (ARF) and sepsis. To promote development toward research independence, he seeks guided training to facilitate mastery of advanced causal effect methodology, qualitative study design, and system-wide intervention development. Research context. Inequitable clinical outcomes are well documented for minoritized patients with ARF and sepsis, but interventions mitigating them are lacking. In part, this is due to a limited understanding of the salient mechanisms most influential to disparities. Among them, harms mediated through socioeconomic disadvantage (defined as access to poor quality socioeconomic resources) and care characteristics related to hospitals that serve the largest proportions of minority patients (often described as minority serving hospitals, or MSHs) are particularly likely to play causal roles. Thus, this proposal aims to clarify the mechanistic roles of these underexplored determinants of health disparities in the context of ARF and sepsis. Specific aims. 1) Characterize the mechanistic role of neighborhood socioeconomic disadvantage on clinical outcome disparities among critically ill patients; 2) Describe clinical processes that influence length of stay disparities for critically ill patients hospitalized at MSHs; and 3) Identify perceived barriers and facilitators of implementing an intervention to reduce hospital readmissions among critically ill patients at MSHs. Research plan. Dr. Chesley will examine relationships between minority identity and clinical outcomes of 200,000 patients across 16 U.S. hospitals. After geocoding four clinically impactful forms of neighborhood-level socioeconomic disadvantage, he will use mediation analyses to elucidate causal roles for these measures. Then, adapting research frameworks from human factors and ergonomics, he will describe the clinical processes that most strongly influence hospital length of stay disparities using semi-structured interviews and direct observation of clinical activities. Lastly, he will conduct semi-structured interviews to identify barriers and facilitators to implementing a systems intervention recommended by the Centers of Medicare and Medicaid Services. Career development plan. Working closely with his mentors and advisors, Dr. Chesley will 1) enhance his mastery of quantitative methods, with emphasis on causal effect methodology and geospatial mapping; 2) develop comprehensive skills in qualitative and mixed-methods study design; and 3) become proficient in developing and testing health systems-level, disparities-mitigating interventions. Environment: The University of Pennsylvania offers an ideal environment to pursue this training, with well- established mentors, a home department heavily dedicated to Dr. Chesley’s success, and several multi- d...