Evaluation of Web-Based and In-Person Methods to Recruit Adults with Type 1 Diabetes for a Technology-Based Exercise Intervention: Prospective Observational Study (Preprint)

BACKGROUND Exercise is essential self-management for type 1 diabetes (T1D), but there are limited data on effective strategies for promoting it. We evaluated a technology-based exercise intervention for adults 18-65 years old with T1D. The COVID-19 social distancing restrictions prompted us to test web-based recruitment methods previously underexplored for this demographic. OBJECTIVE (1) evaluate the effectiveness and cost of using social media news feed advertisements, clinic-based approach, and web-based snowball sampling to reach inadequately active adults with T1D, and (2) compare characteristics of enrollees against normative data and between the different methods. METHODS Participants were recruited between November 2019 and August 2020 for a technology-based exercise intervention study. Method #1: Facebook news feed advertisements ran for five 1-8 day windows targeting adults (18-64yr) in the greater New Haven and Hartford, CT areas with at least one diabetes-related profile interest. If interested, participants completed a webform so that the research team could contact them. Method #2: In-person approach of patients 18-24yr with T1D at clinical visits prior to March 2020. Those interested immediately completed eligibility screening. Older patients could not be approached due to clinic restrictions. Method #3: Snowball sampling by physically active individuals with T1D contacting their peers on Facebook and emails for 48 days with details to contact the research staff to express interest and complete eligibility screening. RESULTS Method #1: Advertisements were displayed to 11,738 unique viewers and attracted 274 clickers (2.33%), of whom 20 (7.3%) volunteered, of whom 8 (40%) were eligible. Fees averaged US $1.20 per click, US $16.44 per volunteer, and US $41.11 per eligible volunteer. Men had lower click rates than women (1.71% vs 3.17%, P < .001) but their responsiveness and eligibility rates did not differ. Method #2: We approached 40 patients of whom 32 (80%) inquired about the study, of whom 20 (63%) volunteered, of whom 2 (10%) were eligible. Personnel costs for arranging in-person approaches averaged US $12.50 per candidate approached, US $15.63 per inquirer, US $25.00 per volunteer, and US $250.00 per eligible volunteer. Method #3: Free snowball sampling generated 13 inquirers, of whom 12 (92%) volunteered, of whom 8 (67%) were eligible. The final enrollees overrepresented usage of continuous glucose monitors and insulin pumps, obesity, and in-target glycemic control. Obesity and above-target glycemic control were more common among those referred by news feed advertisements than snowball sampling (both 88% vs 25%, P = .04). CONCLUSIONS Web-based advertising and recruitment strategies are a promising means to attract adults with T1D to clinical trials and exercise interventions, costs comparing favorably to prior trials despite targeting an uncommon condition (i.e., T1D) and commitment to an intervention. Paid news feed advertisements increased access to higher-risk participants, enabling greater diversity in subject recruitment.