Examining Recruitment and Retention Strategies for Underserved Populations in Thyroid Cancer Clinical Trials: A Cross‐Sectional Analysis

ABSTRACT Objective(s) Thyroid cancer incidence has risen sharply in the US, with disparities in diagnosis and treatment outcomes disproportionately affecting marginalized populations. Despite mandates for diversity in clinical trials, underrepresentation of these groups remains a critical barrier to equitable health outcomes. This study evaluates recruitment and retention strategies in thyroid cancer trials and highlights areas for improvement to enhance inclusivity and generalizability. Methods This cross‐sectional analysis examined the reporting of recruitment and retention strategies for historically marginalized populations in thyroid cancer clinical trials. Following PRISMA guidelines, we searched MEDLINE, Embase, and Cochrane databases for trials published between 2018 and 2023. Eligible studies assessed thyroid cancer treatment interventions and were conducted in locations with a national or multinational Ethnic Fractionalization Index (EFI) of ≥ 0.3. Data extraction included trial characteristics and reporting of recruitment and retention practices. Descriptive analyses were performed using Stata. Results Of 708 articles identified, 28 clinical trials met inclusion criteria. None reported recruitment or retention strategies targeting underrepresented populations, nor established diversity goals. The absence of such strategies highlights persistent gaps in addressing the needs of marginalized groups in thyroid cancer research. Conclusion The lack of effective recruitment and retention strategies in thyroid cancer trials perpetuates the underrepresentation of marginalized populations, limiting the generalizability of findings. To address these disparities, clinical trials must adopt inclusive methodologies and transparent reporting practices, supported by policy changes and stronger enforcement of diversity mandates. These steps are essential for ensuring equitable health outcomes and advancing the quality of thyroid cancer research. Level of Evidence 3