A systematic review of participant diversity in psychedelic-assisted psychotherapy trials.
Psychiatry research March 1, 2025 Stephanie L Haft, Amanda E Downey, Marissa Raymond-Flesch et al. 22 citations
A systematic review of 21 randomized controlled trials of psilocybin- and MDMA-assisted therapies (total 1034 participants) found that participant samples lack diversity. Gender was always reported, race or ethnicity in 76% of trials, and socioeconomic status in 57%. Sexual orientation (9.5%) and immigration status (4.8%) were rarely reported; no study reported gender identity. Compared to the US population and non-psychedelic clinical trials, Black/African-American participants (2.2%) and Hispanic/Latino participants (7.2%) were significantly underrepresented. MDMA trials enrolled more diverse samples than psilocybin trials. Analyses of treatment effects by demographic variables were virtually absent. The findings indicate a need for inclusive recruitment and rigorous reporting to improve generalizability.