Does the Doctor-Patient Relationship Affect Enrollment in Clinical Research?

PURPOSE: Recruiting patients for clinical research is challenging, especially for underrepresented populations, and may be influenced by patients' relationships with their physicians, care experiences, and engagement with care. This study sought to understand predictors of enrollment in a research study among socioeconomically diverse participants in studies of care models that promote continuity in the doctor-patient relationship. METHOD: A study of the effects of vitamin D levels and supplementation on COVID-19 risk and outcomes was implemented from 2020 to 2022 within 2 studies of care models at the University of Chicago that promoted continuity of inpatient and outpatient care from the same physician. Hypothesized predictors of vitamin D study enrollment included patient-reported measures of the care experience (quality of relationship with the doctor and their staff, timely receipt of care), engagement in care (scheduling and completing outpatient visits), and engagement with these "parent" studies (follow-up survey completion). The authors used univariate tests and multivariable logistic regression to examine the association of these predictors with enrollment in the vitamin D study among participants in the parent study intervention arms. RESULTS: Among 773 eligible participants, 351/561 (63%) in the parent study intervention arms enrolled in the vitamin D study, versus 35/212 (17%) in the control arms. Among intervention arm participants, vitamin D study enrollment was not associated with reported quality of communication with or trust in the doctor, or helpful/respectful office staff, but was associated with report of receiving timely care, more completed clinic visits, and higher parent study follow-up survey completion. CONCLUSIONS: Study enrollment may be high in care models with high levels of continuity in the doctor-patient relationship. Rates of clinic involvement, parent study engagement, and experience of receiving timely access to care may better predict enrollment than quality of the doctor-patient relationship.