Assessing the Diversity of Participants in US Colorectal Cancer Clinical Trials: A Comprehensive Review and Meta-Analysis

PURPOSE: Colorectal cancer (CRC) is a significant health concern in the United States. Despite advancements in treatment, disparities in clinical trial representation persist, potentially affecting the generalizability and effectiveness of research findings. METHODS: We conducted a systematic review and meta-analysis of clinical trials on CRC to assess trial representation. Relevant CRC articles were obtained using MEDLINE and Embase. Included studies had to meet the following criteria: they evaluated the effect of an intervention for CRC, were conducted in the United States, were published or posted between January 1, 2018, and December 31, 2023, and were written in English. Data, extracted in a blinded/duplicate fashion, included information about age, race, sex, and ethnicity. A participation-to-disease representation ratio was generated from the data, allowing us to quantitatively assess the representation of patients along with the prevalence of CRC. Outputs were assigned a score of "poor," "fair," or "good" to denote the subgroup representation within each included CRC clinical trial. RESULTS: A total of 25 clinical trials met the inclusion criteria. Regarding race and ethnicity representation, 21 studies received a "poor" rating, four received a "fair" rating, and none received a "good" rating. For sex representation, nine studies received a "good" rating, seven received a "poor" rating, and the remaining did not report sex. CONCLUSION: CRC clinical trials in the United States predominantly over-represented White populations while under-representing Asian, Black, and Hispanic populations. These findings highlight the need for more equitable representation in clinical trials to ensure that diverse populations benefit from medical research advancements.