Financial Incentives to Increase Diversity of Older Participants in a Memory Concerns Registry: A Randomized Clinical Trial

Abstract

Importance: Persons from marginalized racial and ethnic groups and of low socioeconomic status are at high risk of dementia but are underrepresented in clinical trials. Financial incentives may improve representation. Objective: To evaluate the effect of financial incentives on enrollment of county health system patients into a memory concerns registry. Design, Setting, and Participants: Between March 1, 2024, and April 24, 2024, patients 50 years and older without a dementia diagnosis within a single integrated county health system that includes a hospital and 9 outpatient health centers were invited to enroll in the Alzheimer Prevention Trials (APT) Webstudy, an online observational study aimed at accelerating enrollment into Alzheimer disease clinical trials. Interventions: Patients were randomized 1:1:1 to an invitation message (arm 1), a message with a small ($25) enrollment incentive (arm 2), or a message with an enrollment incentive of entry into a $2500 lottery with 1 in 100 odds of award (arm 3). Main Outcomes and Measures: The primary outcome was enrollment, defined as APT Webstudy registration and completion of at least 1 of 2 remote cognitive assessments. Outcomes were measured through April 30, 2024. Results: Of 44844 patients invited to the APT Webstudy, the mean (SD) age was 64.7 (10.1) years, 25447 (56.8%) were women, 25044 (55.8%) had Medicaid insurance, 11347 (25.3%) were Hispanic/Latino, 9526 (21.2%) were non-Hispanic Asian, 6044 (13.5%) were non-Hispanic Black, and 12109 (27%) were non-Hispanic White. A total of 401 participants (0.9%) enrolled in the APT Webstudy. Relative to the message-only arm, participants randomized to the small incentive arm were more likely to enroll (adjusted odds ratio [OR], 1.39; 95% CI, 1.09-1.76; P =.008) in the APT Webstudy while those in the prize incentive arm were not more likely to enroll (adjusted OR, 1.08; 95% CI, 0.84-1.39; P >.99). Enrollment in the prize incentive arm was lower relative to the small incentive arm (adjusted OR, 0.78; 95% CI, 0.61-0.98; P =.04). Secondary heterogeneity analyses indicated that patients of White race (adjusted OR, 1.61; 95% CI, 1.15-2.25; P =.006) and male sex (adjusted OR, 2.40; 95% CI, 1.55-3.75; P