When recruiting research participants through central cancer registries, high response fractions help ensure population-based representation. Using data from 17 recruitment efforts undertaken by the Utah Cancer Registry from 2007 to 2016, we conducted multivariable mixed effects logistic regression to identify case and study characteristics associated with making contact and obtaining cooperation of Utah cancer cases for the following studies: A Population-Based Childhood Cancer Survivor Cohort Study in Utah, Comparative Effectiveness Analysis of Surgery and Radiation for Prostate Cancer (CEASAR Study), Costs and Benefits of Follow-up Care for Adolescent and Young Adult Cancers, Genetic Analysis of Digestive Cancers, Genetic Epidemiology of Breast Cancer, Genetic Epidemiology of Chronic Lymphocytic Leukemia, Genetic Epidemiology of Multiple Myeloma, Head and Neck Cancer Susceptibility Genes, Impact of Remote Familial Colorectal Cancer Risk Assessment and Counseling (Family CARE Project), Medullary Thyroid Carcinoma (MTC) Surveillance Study Osteosarcoma Surveillance Study, the Prostate Cancer Outcomes Study, Risk Education & Assessment for Cancer Heredity Project (REACH Project), and the Utah Cancer Survivors Study. Characteristics associated with lower odds of contact included Hispanic ethnicity (Odds Ratio [OR] = 0.34, 95% Confidence Interval [CI]: 0.27, 0.41), non-white race (OR = 0.46, 95% CI: 0.35, 0.60), and younger age at contact. Years since diagnosis was inversely associated with making contact. Non-white race and age ≥60 had lower odds of cooperation. Study features with lower odds of cooperation included longitudinal design (OR = 0.50, 95% CI: 0.41, 0.61) and study brochures (OR = 0.70, 95% CI: 0.54, 0.90). Increased odds of cooperation were associated with including a questionnaire (OR = 3.19, 95% CI: 1.54, 6.59), postage stamps (OR = 1.60, 95% CI: 1.21, 2.12), and incentives (OR = 1.62, 95% CI: 1.02, 2.57). Among cases not responding after the first contact, odds of eventual response were lower when >10 days elapsed before subsequent contact (OR = 0.71, 95% CI: 0.59, 0.85). Obtaining high response is challenging, but study features identified in this analysis support better results when recruiting through central cancer registries.
