Principal investigator gender and clinical trial success: analysis of over 3000 obstetrics and gynecology trials.

backgroundIn obstetrics and gynecology (OBGYN) research, gender disparities permeate through leadership, funding, promotion, mentorship, publishing, compensation, and publicity. Few studies have investigated OBGYN clinical trial leadership as it relates to investigator gender. Thus, we undertook an investigation of principal investigator (PI) gender and clinical trial success.

objectiveTo characterize United States (US) OBGYN clinical trials by PI gender and analyze the association between PI gender and features of trial success. STUDY

designThis is a cross-sectional study of all US-based obstetric and gynecologic clinical trials registered on ClinicalTrials.gov (2007-2020). We examined associations between PI gender (ie, led by women, men, or both) and four primary outcomes that capture clinical trial success: early discontinuation (ie, absence of early discontinuation is a feature of success), reporting of complete trials to ClinicalTrials.gov, publication in a peer-reviewed journal, and clinical trial participant diversity (reporting of racial and ethnic diversity data and representation of diverse cohorts). Multivariable analyses controlled for subspecialty, multiple PI status, source of funding, primary purpose, phase, number of arms, enrollment, year of trial registration, blinding, oversight by a Data Safety Monitoring Committee, and number of study sites. Sensitivity analysis accounted for individual PI who led multiple clinical trials. Univariable and multivariable logistic regression analysis models were applied. We conducted multiple imputation for missing covariable data. There were no missing exposure or outcome data in the final cohort.

resultsWe reviewed 12,635 clinical trials focused on OBGYN. Of the 4342 trials with at least one site in the US, PI names were available for 3087 trials (71.1%). The majority of OBGYN trials were women-led (women 1696, 54.9%; men 1272, 41.2%, coled 119, 3.9%). A greater proportion of obstetrics trials (617, 60.0%) were women-led than gynecology trials (1079, 52.4%). Family planning had the greatest proportion of women-led trials (145, 74.7%), whereas reproductive endocrinology and infertility had the lowest (50, 30.9%). A greater proportion of industry-funded trials were led by men (123, 64.7%). In adjusted analysis, women-led trials had lower odds of early discontinuation (men-led reference; women-led adjusted odds ratio [aOR] 0.58, 95% confidence interval [CI] 0.44, 0.77). Women-led trials reported results less frequently (men-led reference; women-led aOR 0.52, CI 0.40-0.62) but no significant difference was seen in publication (men-led reference; women-led aOR 1.02, CI 0.57, 1.81). Women-led trials had greater odds of reporting race and ethnicity participant data (men-led reference; aOR 1.87, CI 1.27-2.47) but there was no difference in cohort diversity by PI gender.

conclusionWomen investigators lead approximately half of OBGYN clinical trials in the US. Women-led trials discontinue less frequently, publish at similar rates, and include data on diversity more frequently than men-led trials. Women are as successful as men in conducting clinical trials and, in certain domains, more successful. Our findings place the impetus on the OBGYN professional ecosystem to support women's academic careers.