To characterize the representation of various demographic groups, including gender, age, primary language, race, ethnicity, marital status, religion and country of origin, in a department-wide clinical database and biobanking study. Materials/Methods: A total of 10,114 patients who presented for radiotherapy planning between Oct 14, 2016 and Mar 15, 2020 were identified using an institutional resource. Among those deemed eligible for the study by treating clinicians, 3421 patients were consented. Self-reported demographics data were obtained from a research patient data registry. Associations between the consent status and the demographic characteristics were analyzed using logistic regression models, and the odds ratios adjusted for other covariates (OR) with 95% confidence interval (CI) were reported. The Cochran-Mantel-Haenszel (CMH) and Breslow-Day tests were used to assess potential interactions between language and ethnicity and marital status and gender and to evaluate confounding effects of ethnicity and gender. Results: After excluding participants 18 years and under or those with incomplete demographics data, a total of 9,388 patients were included in the analysis. Among these, 3,276 were consented. Consent rates to the study varied significantly across all demographic groups except for country of origin. Men were more likely than women to enroll in the study (OR, 1.29; 95% CI, 1.18-1.42; P < 0.001). Patients in the 65-74 (OR, 0.86; 95% CI, 0.77-0.95; P < 0.05) and older than 75 years old (OR, 0.75; 95% CI, 0.67-0.85; P < 0.001) age groups were less likely to consent compared to patients in the 45-64 years old group. English speaking patients were more likely to consent than non-English speaking patients (OR, 9.61; 95% CI, 6.94-13.69; P < 0.001). Compared to Whites, Hispanics (OR, 0.47; 95% CI, 0.26-0.80; P < 0.05) and African Americans (OR, 0.40; 95% CI, 0.32-0.50; P < 0.001) were less likely to consent. Participants who were married or in a partnership exhibited a higher consent rate than single patients (OR, 1.12; 95% CI, 1.01-1.23; P < 0.05). Religious patients were less likely to consent than non-religious patients (OR, 0.78; 95% CI, 0.69-0.88; P < 0.001). There were no significant interactions found between language and ethnicity and marital status and gender. Neither ethnicity nor gender exhibited significant confounding effects for rate of consent. Conclusion: Women, the elderly, non-English speakers, racial and ethnic minorities, single, and religious individuals showed lower consent rates to the study compared to men, younger, English speakers, Whites, married, and non-religious patients. These results demonstrate demographic disparities that could influence the results of future research performed using this departmental biobanking database resource, and identify areas for improvement.
