JMIR Publications

ABSTRACT

Background:

Online recruitment for research studies is increasingly popular and necessary. When compared to traditional methods of recruitment, these methods may enable researchers to reach more diverse participants in less time. Social media use is highly prevalent among adolescents, and the unique context of social media may be particularly important for the recruitment of sexual minority young people who would not be captured by traditional methods.

Objective:

This paper describes the details of a national online study recruitment approach aimed at sexual minority adolescents across the United States, focusing on important details of this relatively novel approach, including cost, time efficiency, and retention outcomes.

Methods:

This study recruited sexual minority adolescents aged 14–17 years living in the United States through targeted advertisements on Facebook, Instagram, and YouTube and through respondent-driven sampling (RDS). Potential participants completed eligibility screening surveys and were automatically directed to a baseline survey if eligible. After baseline survey completion, additional data checks were implemented and remaining participants were contacted for recruitment into a longitudinal study (surveys every 6 months for 3 years).

Results:

Recruitment lasted 44 weeks, And 9,843 participants accessed the initial screening survey, with 2,732 meeting eligibility criteria and completing the baseline survey. Of those, 2,558 were determined to have provided nonfraudulent, useable study data and 1,076 subsequently enrolled in the longitudinal study. Of the baseline sample, 79% was recruited through Facebook and Instagram, 3% through YouTube, and 18% through RDS. The average cost of recruiting a participant into the study was $12.98, but varied by method or platform, with a realized cost of $13 per participant on Facebook and Instagram, $24 on YouTube, and $10 through RDS. Participant differences (sex assigned at birth, race and ethnicity, sexual orientation, region, and urbanicity) were identified between platforms and methods both in terms of overall number of participants and cost per participant. Facebook and Instagram was the most time efficient (approximately 15 days to recruit 100 participants), whereas RDS was the least (approximately 70 days for 100 participants). Participants recruited through YouTube were the most likely to be longitudinally retained, followed by Facebook and Instagram and then RDS.

Conclusions:

Overall, large differences exist in study recruitment cost and efficiency when using social media and RDS. In this study, RDS was the most cost-efficient but least time-efficient method, whereas Facebook and Instagram was the most time efficient and YouTube resulted in the highest rate of longitudinal retention. Demographic, region, and urbanicity differences in recruitment methods highlight the need for attention to demographic diversity when planning and implementing recruitment across platforms. Finally, it is more cost effective to retain than recruit samples, and this study provided evidence that with thorough screening and data-quality practices, social media recruitment can result in diverse, highly involved study populations.