Correlates of knowledge of clinical trials among US adults: Findings from the 2020 Health Information National Trends Survey

Background: Knowledge about clinical trials affects efficient and equitable clinical trial recruitment and retention. This study explored correlates of clinical trial knowledge in a nationally representative sample of US adults. Methods: Cross-sectional data from the 2020 Health Information National Trends Survey (HINTS 5, Cycle 4) were evaluated. There were 3,865 responses in the full dataset; 2,648 remained after eliminating respondents without complete data for all covariates of interest. Participants were asked, "How would you describe your level of knowledge about clinical trials?" The response options "know a little bit" and "know a lot" were combined and compared to the response option "don't know anything." Covariates of interest included patient-provider communication, history of medical conditions, eHealth use, knowledge of clinicaltrials.gov, prior invitation to join a clinical trial, and socio-demographic factors. Results: Participants with a history of cancer were 1.6 times more likely [CI 1.2, 2.2] to have knowledge of clinical trials. Participants who used electronic means to look for health information were 1.7 times more likely [CI 1.2, 2.4] to have knowledge of clinical trials. Participants who had heard of the website clinicaltrials.gov had 5.1 times greater odds of knowing about clinical trials [CI 2.6, 10.3] and 4.5 greater odds if they had been invited to participate in a clinical trial [CI 2.0, 9.8]. College graduates had higher odds than others. Conclusion: Several factors affect clinical trial knowledge in US adults. Findings from this study may inform interventions to raise awareness about clinical trials and thereby, potentially improve enrollment.