OBJECTIVE: The objective of this study was to examine the representation of historically marginalized racial and ethnic groups in pediatric obesity clinical trials. METHODS: We performed a cross-sectional analysis of clinical trials in pediatric obesity (participants aged ≤18 years) that were registered in ClinicalTrials.gov, were completed from January 2013 to August 2023, and were conducted in the United States. We quantified disparities in trial enrollment by calculating the enrollment-prevalence disparity (EPD) for each racial and ethnic group. RESULTS: A total of 260 trials met eligibility criteria, of which 128 trials (49.2%) reported race and/or ethnicity data. Enrollment of White, Hispanic, and Black children roughly reflects disease burden in these populations. However, relative to disease burden, Asian (EPD, -3.7%
IQR, -3.7% to 1.8%
p <
0.0001), American Indian and Alaska Native (EPD, -2.1%
IQR, -2.1% to -2.1%
p <
0.0001), and Native Hawaiian or other Pacific Islander (EPD, -0.6%
IQR, -0.6% to -0.6%
p <
0.0001) children were significantly underrepresented in these trials. CONCLUSIONS: With the exception of Black and Hispanic children, historically marginalized racial groups were underrepresented in pediatric obesity trials, signifying a need to improve diversity of participants in these trials. Additionally, there are substantial gaps in the documentation of race and ethnicity information. Concerted efforts are needed to ensure adequate reporting of race and ethnicity information in clinical trials.