Recruitment of men who have sex with men for large HIV intervention trials: analysis of the EXPLORE Study recruitment effort.

Testing HIV prevention strategies requires that researchers recruit participants at high risk of HIV infection. Data from the EXPLORE Study, a behavioral intervention trial involving men who have sex with men (MSM), were used to examine the relationship between recruitment strategies and participant characteristics, sexual risk behaviors and HIV incidence. The EXPLORE Study used a wide variety of recruitment strategies; no one strategy accounted for more than 20% of enrolled men. Younger men and men of color were more likely to be recruited through club and bar outreach, friend referral, and street outreach. Men reporting 10 or more sexual partners were more likely to be recruited through advertising and street outreach. Men reporting unprotected sex were more likely to be recruited through clinic referrals. HIV incidence did not significantly differ by recruitment strategy. Our findings support the need for a wide range of recruitment strategies in attracting MSM at high risk for HIV into clinical studies.