Explaining Cancer Clinical Trial Willingness: The Relative Roles of Information Empowerment and Interpersonal Discrimination

Background Racial and ethnic disparities in cancer trial participation persist. Structural racism frameworks emphasize medical mistrust and discrimination in healthcare, whereas communication inequality frameworks emphasize gaps in awareness, knowledge, and exposure. Guided by both, we examined racial and ethnic differences in trial willingness, whether interpersonal discrimination in healthcare and information empowerment (trial knowledge, awareness, information confidence, and prior experience) account for them, and whether the two mechanisms are related or interact. Methods Data ( N = 2,812) came from a 2023 multistate cancer focused needs assessment in Arizona, Florida, and the Midwest. Race and ethnicity were categorized as non-Hispanic (NH) White, NH Black, Other NH, and Hispanic (any race). Willingness was modeled using ordinal logistic regression. Model 1 adjusted for sociodemographic characteristics and region; Model 2 added discrimination; Model 3 added information empowerment instead; Model 4 added both. Whether the two mechanisms interact was tested using a likelihood ratio test. Results In Model 1, Hispanic and Other NH adults were less willing to join a cancer clinical trial than NH White adults, whereas NH Black adults did not differ significantly. Discrimination (Model 2) only slightly attenuated these differences, whereas information empowerment (Model 3) moved them toward parity. In Model 4, lower willingness persisted only for Other NH adults. All four information empowerment measures and healthcare discrimination were associated with greater willingness. Per standard deviation, trial knowledge showed a stronger association than discrimination. Among the continuous predictors, perceived clinical trial knowledge showed the strongest association. These two mechanisms were related but did not interact. Conclusions Equity efforts should prioritize trial communication and proactive invitations while continuing to address disrespectful care and structural barriers to trial access. The difference persisting among Other NH adults warrants a disaggregated study.