Diversity in Enrollment to Clinical Trials for Cataract Medicine and Surgery: A Meta-Analysis

Abstract

Purpose: To investigate sex, racial, and ethnic disparities in patient enrollment across cataract trials registered in the United States (US). Setting: Participants enrolled in high-quality (reduced risk of bias), US-registered (on clinicaltrials.gov), cataract-related randomized controlled trials (RCTs). RCTs must be completed, have employed double or greater masking, and have published results through the registry or a scholarly journal. Design: Cross-Sectional database study. Methods: Trial (study sponsor country, study site location, trial initiation year, study phase, and study masking) and demographic data (sex, race, and ethnicity according to US reporting guidelines) were collected. The Global Burden of Disease database provided sex-based cataract disease burdens. Pooled participation-to-prevalence ratios (PPRs) with 95% confidence intervals (CI) were calculated for female sex, with values between 0.8 and 1.2 constituting sufficient study enrollment. Kruskal-Wallis tests (alpha=0.05) with subsequent post-hoc comparisons were used to evaluate demographic representations stratified by trial characteristics. Results: From 864 records, we identified 100 clinical trials (N=67874), of which 97 (N=67697) reported sex demographics with a pooled female PPR of 0.89, 95%CI [0.85,0.94]. Of the 67697 total participants, the absolute female enrollment was 19062 (28.16%). Ethnicity and race were reported in 9 (N=1792) and 26 trials (N=23181), respectively. Among trials that reported race, most were Caucasian (N=19574;84.44%). Conclusions: High-quality, US-registered, cataract trials enrolled acceptable proportions of females. However, the absolute number of female and racialized participants was low. Race and ethnicity were underreported. Disparity trends predominately held across secondary variables. To promote generalizability, future trials should pursue equitable demographic enrollment.