Affiliation:
1. Department of Supportive Care Princess Margaret Cancer Centre University Health Network Toronto Ontario Canada
2. Department of Psychiatry University of Toronto Toronto Ontario Canada
3. Department of Biostatistics Princess Margaret Cancer Centre University Health Network Toronto Ontario Canada
4. Department of Community Health and Epidemiology University of Saskatchewan Saskatoon Saskatchewan Canada
5. Radiation Medicine Program Princess Margaret Cancer Centre University Health Network Toronto Ontario Canada
6. Cancer Clinical Research Unit Princess Margaret Cancer Centre University Health Network Toronto Ontario Canada
7. Division of Medical Oncology and Haematology Princess Margaret Cancer Centre Toronto Ontario Canada
8. Department of Medicine University of Toronto Toronto Ontario Canada
9. Department of Health Policy and Management Harvard T. H. Chan School of Public Health Boston Massachusetts USA
10. Department of Markets, Public Policy, and Law Boston University Questrom School of Business Boston Massachusetts USA
11. Department of Radiation Oncology University of Toronto Toronto Ontario Canada
Abstract
AbstractIntroductionDisparities in clinical trials (CTs) enrollment perpetuate inequities in treatment access and outcomes, but there is a paucity of Canadian data. The objective of this study was to examine disparities in cancer CT enrollment at a large Canadian comprehensive cancer center.MethodsRetrospective study of CT enrollment among new patient consultations from 2006 to 2019, with follow‐up to 2021 (N = 154,880), with the primary outcome of enrollment as a binary variable. Factors associated with CT enrollment were evaluated using multivariable Bayesian hierarchical logistic regression with random effects for most responsible physician (MRP) and geography, adjusted for patient characteristics (sex, age, language, geography, and primary care provider [PCP]), area‐level marginalization (residential instability, material deprivation, dependency, and ethnic concentration), disease (cancer site and stage), and MRP (department, sex, language, and training). A sensitivity analysis of the cumulative incidence of enrollment was conducted to account for differences in disease type and follow‐up length.ResultsCT enrollment was 11.2% overall, with a 15‐year cumulative incidence of 18%. Lower odds of enrollment were observed in patients who were female (adjusted odds ratio [AOR], 0.82; 95% confidence interval [CI], 0.78–0.86), ≥65 years (AOR vs. <40, 0.61; 95% CI, 0.56–0.66), non‐English speakers (0.72; 95% CI, 0.67–0.77), living ≥250 km away (AOR vs. <15 km, 0.71; 95% CI, 0.62–0.80), and without a PCP. Disease characteristics accounted for the largest proportion of observed variation (20.8%), with significantly greater odds of enrollment in patients with genitourinary cancers and late‐stage disease.ConclusionSignificant sociodemographic disparities were observed, suggesting the need for targeted strategies to increase diversity in access to cancer CTs in Canada.