Insufficient Reporting of Race and Ethnicity in Breast Cancer Clinical Trials

Reporting race and ethnicity in clinical trial publications is critical for determining the generalizability and effectiveness of new treatments. This is particularly important for breast cancer, in which Black women have been shown to have between 40 and 100% higher mortality rate yet are underrepresented in trials. Our objective was to describe changes over time in the reporting of race/ethnicity in breast trial publications.

We searched ClinicalTrials.gov to identify the primary publication linked to trials with results posted from May 2010-2022. Statistical analysis included summed frequencies and a linear regression model of the proportion of articles reporting race/ethnicity and the proportion of non-White enrollees over time.

A proportion of 72 of the 98 (73.4%) studies that met inclusion criteria reported race/ethnicity. In a linear regression model of the proportion of studies reporting race/ethnicity as a function of time, there was no statistically significant change, although we detected a signal toward a decreasing trend (coefficient for quarter = -2.2, p = 0.2). Among all studies reporting race and ethnicity over the study period, the overall percentage of non-White enrollees during the study period was 21.9%, [standard error (s.e.) 1.8, 95% confidence interval (CI) 18.4, 25.5] with a signal towards a decreasing trend in Non-White enrollment [coefficient for year-quarter = -0.8 (p = 0.2)].

Our data demonstrate that both race reporting and overall representation of minority groups in breast cancer clinical trials did not improve over the last 12 years and may have, in fact, decreased. Increased reporting of race and ethnicity data forces the medical community to confront disparities in access to clinical trials. This may improve efforts to recruit and retain members of minority groups in clinical trials, and over time, reduce racial disparities in oncologic outcomes.