Racial and gender disparities in traumatic brain injury clinical trial enrollment

OBJECTIVE Despite the increasing number of women and racial/ethnic minorities sustaining traumatic brain injuries (TBIs), they are underrepresented in TBI clinical trials. This study aimed to evaluate gender and racial diversity in enrolled cohorts of TBI clinical trials to identify trends and predictors of increased disparity over time. METHODS The authors reviewed TBI clinical trials with reported results registered on the website ClinicalTrials.gov between 2008 and 2022. The studies were assessed for the proportion of women and racial/ethnic minorities enrolled as well as their reporting of race- and gender-specific characteristics such as gender ratio (GR) and Racial Diversity Index (RDI). Further study parameters, including year and duration, phase, trial design, type of funding, and trial completion, were also included. RESULTS One hundred thirty-five clinical trials met inclusion criteria, of which 65 and 134 reported race and gender, respectively. Twenty-five trials were found to have existing racial disparity (RDI < 1). Comparatively, industry-funded trials had a 26% greater likelihood of racial disparities (p = 0.026), whereas federally funded trials were 30% less likely to demonstrate racial disparities (p = 0.031). Sixty-six trials had gender disparities (GR < 0.4) present, with federally funded trials showing 37.1% greater rates of gender disparity (p < 0.001, adjusted OR 5.47, 95% CI 2.26–14.25). The impact of funding source on race and gender remained significant despite adjusting for other covariates in the multivariate analyses. Racial disparity was negatively correlated with trial completion rate (p < 0.001). Disparities were not found to improve over the 14-year time span. CONCLUSIONS Racial and gender disparities in TBI clinical trial enrollment persist, and the lack of diversity may lead to biased evidence-based medicine. Efforts should be made to increase the representation of women and racial/ethnic minorities in TBI clinical trials to ensure equitable access to effective treatments for all populations.