UCLA

Objectives

We examined whether and how an HIV prevention diffusion-based intervention spread throughout participants' online social networks and whether changes in social network ties were associated with increased HIV prevention and testing behaviors.

Methods

We randomly assigned 112 primarily racial/ethnic minority men who have sex with men (MSM) to receive peer-delivered HIV (intervention) or general health (control) information over 12 weeks through closed Facebook groups. We recorded participants' public Facebook friend networks at baseline (September 2010) and follow-up (February 2011), and assessed whether changes in network growth were associated with changes in health engagement and HIV testing.

Results

Within-group ties increased in both conditions from baseline to follow-up. Among the intervention group, we found a significant positive relation between increased network ties and using social media to discuss sexual behaviors. We found a positive trending relationship between increased network ties and likelihood of HIV testing, follow-up for test results, and participation in online community discussions. No significant differences were seen within control groups.

Conclusions

Among high-risk MSM, peer-led social media HIV prevention interventions can increase community cohesion. These changes appear to be associated with increased HIV prevention and testing behaviors.