Key barriers against racial and ethnic minority participation in U.S. clinical trials


  • Ashley S. Bae College of Nursing, The Ohio State University Graduate School, Columbus, Ohio, United States



Clinical trial participation, Barriers, Diversity, Underrepresented minorities, Race, Ethnicity


Despite the United States’ (U.S.) longstanding history of promoting a melting pot nation of people from diverse racial and ethnic backgrounds all capable of achieving the American Dream, it is argued that the U.S. is failing to deliver high quality healthcare to all of its constituents equally. The widely seen health disparities of ethnic minority groups endure has extended into the parallel field of clinical research and clinical trials. There is a staggering gap between the percentage of White clinical trial participants compared to clinical trial participants of racially and ethnically diverse minority groups in U.S. clinical trials. Underrepresentation of minority groups in clinical trials dismisses opportunities to identify potential serious sub-group safety or efficacy signals, open doors to access life-saving treatments, and ultimately improve the standard of evidence-based medicine in the United States. Current literature on this issue frequently reiterates the following five key barriers underrepresented minority groups face against clinical trial participation: mistrust, lack of awareness and access, cultural and language barriers, investigator and provider bias, and financial burdens. A deeper dive into understanding each barrier will be critical in implementing changes with actions and in perspectives in order to address the issue of poor racial and ethnic representation in clinical trial populations.


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