Abstract Background Recruiting participants for health research can be challenging. Virtual recruitment strategies are growing, including radio, email, and social media advertising. Prior research demonstrates a lack of clarity to which strategies are most effective, and further reporting is necessary to maximize recruitment success. This study aimed to observe differences in enrolment and uptake data over time across virtual recruitment strategies (paid and unpaid social media advertisements, not-for-profit organizations, radio), and evaluate the visibility, cost, and engagement of each recruitment strategy, when available. Methods Post-hoc mixed-methods evaluation of virtual recruitment strategies (radio, not-for-profit organizations, paid and unpaid social media advertisements) from two mHealth implementation studies. Data were collected regarding number of enrolments over time, advertisement visibility (number of advertisements, reach, demographics), cost, and engagement (post reactions, comments, shares). Data were analyzed using summary statistics and inductive content analysis. Results Virtual recruitment strategies enabled enrolment of 1548 participants in 9-months. Observations indicated not-for-profit health organization promotions and paid social media advertisements were associated with largest increases in recruitment. Paid advertisements ( n = 15) had broad visibility across all Australian states and territories, reaching mostly females and people aged 65 + years, were low-cost, with high engagement. Engagement via comments on social media advertisements may have increased visibility through referrals, sharing personal experiences and connecting with one another. Conclusion Not-for-profit organization promotions and paid social media advertisements are effective virtual recruitment strategies which may facilitate study visibility and increased recruitment. These findings are beneficial for researchers wishing to apply virtual recruitment strategies to future health research studies.
Raeside et al. (Thu,) studied this question.