A Comparison of Participant Demographics Across Co-Designed Recruitment Methods to Two Student Mental Health Trials: Cross-Sectional Observational Study.
Dooley J, Whitmore A, Gillett E, Watkins E • JMIR formative research • 2026
Social media recruitment for student mental health trials attracted younger, more gender-diverse, more LGBTQIA+, and more disabled participants compared to other recruitment methods, but did not differ in ethnicity.
Key Findings
Results
Social media recruitment yielded a higher proportion of gender-diverse students and fewer male students compared to other recruitment methods.
Gender difference was statistically significant (χ²2=8.34, P=.02)
Gender-diverse students: 7% via social media (27/370) vs 4% via other methods (30/711); 95% CI 3.4%-13.7%
Male students: 4% via social media (35/370, 95% CI 3.4%-13.7%) vs 7% via other methods (99/711, 95% CI 1.6%-9.8%)
Total sample included 842 participants recruited via social media and 1527 recruited by other methods
Results
Participants recruited via social media were significantly younger than those recruited through other methods.
Mean age difference of -3.49 years (SE=0.31, 95% CI [-3.94 to -3.04])
t1927.5=15.146, P<.001
This was one of the largest observed differences between the two recruitment groups
Results
A significantly higher proportion of students recruited via social media identified as LGBTQIA+ compared to those recruited through other methods.
51% of social media recruits identified as LGBTQIA+ (180/351, 95% CI 41.3%-60.6%) vs 37% of other-method recruits (350/711, 95% CI 28.2%-46.8%)
χ²1=17.87, P<.001
This finding supports social media's cited ability to engage 'hard-to-reach' participants
Results
Students recruited via social media were more likely to report a disability than those recruited through other methods.
27.5% of social media recruits reported a disability (103/375, 95% CI 19.7%-37.0%) vs 21.3% of other-method recruits (154/723, 95% CI 14.4%-30.3%)
χ²1=4.90, P=.03
All tests used α=.05
Results
There was no statistically significant difference in ethnicity between participants recruited via social media and those recruited through other methods.
χ²1=2.4609, P=.12
This was the only demographic characteristic tested that did not differ significantly between recruitment groups
The sample comprised UK university students consenting to participate in 2 mental health trials over a 12-month recruitment period
Results
An Instagram carousel advert, developed with student advisory input, led to a boost in participant recruitment, though recruitment fluctuated across the academic year and dropped completely over summer months.
10 different adverts were trialed over the 12-month recruitment period across Meta and TikTok platforms
Advert performance was evaluated using Meta/TikTok business data for reach and link clicks, Google Analytics for website traffic, and REDCap for screening consent and enrollment
Recruitment numbers dropped completely over the summer months, highlighting a seasonal limitation of university-based recruitment
The student advisory group advised on content, platform, and timing of engagement
Methods
A co-designed social media recruitment strategy involving a student advisory group was implemented across two student mental health trials enrolling 2369 UK university students.
Total consenting participants: 2369 UK university students across 2 mental health trials
842 participants were recruited via social media; 1527 were recruited by other methods
The advisory group guided content, platform selection, and timing of social media engagement
Demographic comparisons examined ethnicity, gender, sexual orientation, disability status, and university attended using chi-square and t tests
What This Means
This research suggests that the way researchers recruit people for mental health studies significantly affects who ends up participating. The study compared nearly 2,400 UK university students who joined one of two mental health trials, looking at whether those recruited through social media (Instagram and TikTok) differed demographically from those recruited through other on-campus methods. The researchers worked closely with a student advisory group to design their social media content, and tested 10 different adverts over a year.
The findings show that social media recruitment attracted a notably different group of people. Those recruited via social media were on average about 3.5 years younger, more likely to identify as gender-diverse, more likely to identify as LGBTQIA+ (51% vs 37%), and more likely to report having a disability (27.5% vs 21.3%). Ethnicity was the one characteristic that did not differ between the groups. An Instagram carousel advert was particularly effective, though recruitment was uneven throughout the year and stopped almost entirely over the summer when students were not on campus.
This research suggests that relying on just one recruitment method in university-based health research may unintentionally exclude certain groups. Social media appears to be especially effective at reaching younger students and those from LGBTQIA+ and gender-diverse communities — groups that may be underrepresented in traditional campus recruitment. The practical takeaway from this study is that research teams planning clinical trials with student populations should budget adequate time and resources to develop multiple, complementary recruitment strategies in order to capture a more diverse and representative sample of participants.
Dooley J, Whitmore A, Gillett E, Watkins E. (2026). A Comparison of Participant Demographics Across Co-Designed Recruitment Methods to Two Student Mental Health Trials: Cross-Sectional Observational Study.. JMIR formative research. https://doi.org/10.2196/76018