JMIR Publications

ABSTRACT

Background:

Participant recruitment is a persistent barrier to clinical trials, particularly in primary care, where fixed funding timelines intensify pressure to enrol rapidly and traditional clinician-mediated and community-based methods can be slow and resource-intensive. Direct-to-patient (DTP) digital recruitment through social media offers a potential alternative, but real-world evidence in primary care trials requiring rapid enrolment remains limited.

Objective:

To evaluate the effectiveness and efficiency of a multi-modal recruitment strategy combining primary care network outreach with DTP social media advertising in achieving enrolment targets within a constrained timeframe in a fully remote primary care digital therapeutic trial, and to describe its impact on recruitment performance, participant retention, and engagement.

Methods:

The RiSolve study was a single-arm, fully remote primary care trial of a digital therapeutic for women with bothersome overactive bladder symptoms, delivered through the Irish primary care clinical trials network with a target of approximately 45 participants within an eight-week window. Recruitment combined traditional outreach (approximately 150 general practices, urogynaecology units, community and pharmacy promotion, and snowball referral) with DTP paid advertising on Meta (Facebook and Instagram) and Google. The recruitment funnel, campaign metrics (impressions, click-through rate, cost per click, and cost per enrolled participant), and retention (Week 8 completion) were summarised descriptively.

Results:

Of 208 expressions of interest, 204 (98.1%) were generated through social media; none of the 46 enrolled participants were recruited via traditional pathways. The enrolled cohort's mean age (60 years) and body mass index (27.8 kg/m²) were consistent with the population subgroups reported to carry the highest burden of OAB. The target was achieved three weeks ahead of schedule (47 participants consented over five weeks; mean 9.4 per week), with an 83.9% pre-screening-to-consent conversion. The Meta campaign achieved a click-through rate of 1.80% and a cost per click of €0.13 on a spend of €879.08, at €19.11 per enrolled participant. Engagement closely tracked campaign delivery, with 94.7% of expressions of interest recorded while advertising was live. Retention was 82.6% (38/46).

Conclusions:

A direct-to-patient digital recruitment strategy enabled rapid, cost-efficient enrolment in a fully remote primary care trial, meeting the target ahead of schedule while traditional methods contributed no enrolments. Recruited participants showed high retention, countering concerns that digitally recruited cohorts are difficult to retain. These findings support direct-to-patient digital recruitment as a viable strategy for time-constrained, decentralised primary care trials. Future work should incorporate end-to-end conversion tracking and directly compare recruitment pathways across a range of other therapeutic areas. Clinical Trial: ClinicalTrials.gov NCT07206446; https://clinicaltrials.gov/study/NCT07206446