A systematic review of participant diversity in psychedelic-assisted psychotherapy trials.
Stephanie L Haft, Amanda E Downey, Marissa Raymond-Flesch, Gisele Fernandes-Osterhold, Ellen R Bradley, Aoife O'Donovan, Joshua Woolley
Psychiatry research March 1, 2025 DOI: 10.1016/j.psychres.2025.116359 via PubMed
Summary
AI-generated from the abstractA 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.
Study at a glance
| Characteristics | Systematic review Randomized Peer reviewed |
|---|---|
| Sample size | 1,034 |
| Population | Participants in randomized controlled trials of psilocybin- and MDMA-assisted therapies |
| Topics | MDMA Psilocybin |
| Keywords | Psychedelic research MDMA Therapy Systematic review Clinical diversity Psilocybin trials |
| Citations | 22 |
| Key finding | Black/African-American and Hispanic/Latino participants were significantly underrepresented in psychedelic-assisted psychotherapy trials compared to their representation in the US population and non-psychedelic clinical trials. |
Abstract
A lack of diverse and representative participant samples in mental health intervention research perpetuates mental health disparities. This issue has become a salient concern in studies of psychedelic-assisted psychotherapy (PAT), which is emerging as a promising mental health intervention. This systematic review evaluates the reporting, representation, and analysis of participant sociodemographic characteristics in randomized controlled trials (RCTs) of PAT. A total of 21 RCTs of psilocybin- and 3,4-methylenedioxy methamphetamine (MDMA)-assisted therapies (N = 1034) are summarized. Participants' gender (100%) and race or ethnicity (76%) were frequently reported, with socioeconomic status (SES) sometimes (57%) reported using heterogeneous metrics. Sexual orientation (9.5%) and immigration status (4.8%) were rarely reported, and no studies reported gender identity. Compared to their representation in the US population and non-psychedelic clinical trials, Black/African-American participants (2.2%) and Hispanic/Latino participants (7.2%) were significantly underrepresented in PAT RCTs. MDMA trials enrolled more diverse participant samples than psilocybin trials. Analyses on treatment effects based on demographic variables were virtually nonexistent. These findings underscore the need for more inclusive recruitment strategies, along with more rigorous reporting, to improve the generalizability of PAT research.