Federally Funded Randomized Controlled Trials Increase Analysis and Reporting of Study Outcomes by Sex, Race, and Ethnicity

Background: We previously examined National Institutes of Health (NIH)-funded randomized controlled trials (RCTs) published in 2004, 2009, and 2015 and found low compliance with NIH policies on inclusion, analysis, and reporting results for female and minoritized subgroups, with no improvement over time. We conducted a fourth wave of data collection using RCTs published in 2021, comparing current results with previous years.Materials and Methods: The authors used PubMed to find 657 RCTs published in print in 14 leading US medical journals in 2021. Of those, 93 (14.2%) were eligible for analysis. We reviewed all parts of eligible studies and any published commentary. Fisher's exact statistics compared proportions of studies analyzing or reporting results for subgroups in 2021 compared with RCTs studied in previous waves. Posthoc analysis compared eligible RCTs about the Covid-19 pandemic to eligible RCTs on other topics.Results: Twenty-five of 93 studies (26.9%) analyzed or reported outcomes by race or ethnicity, an increase over previous years (p < 0.01). Among 79 RCTs with participants of both sexes, the median proportion of female participants was 43%. Moreover, 34 (43.0%) reported an outcome by sex, included sex as a covariate in statistical analysis, or reported results by sex, also an increase over previous waves (p < 0.01). Eleven eligible studies (11.8%) were on a SARS-CoV-2 topic; there was no difference between SARS-CoV-2 RCTs and RCTs on other topics.Conclusions: Analysis and reporting by sex, race, and ethnicity for NIH-funded RCTs published in 2021 significantly increased from previous waves, despite no corresponding increase in enrollment.