Finding and recruiting the highest risk HIV-negative men who have sex with men.

This study compared the ability of different field and online recruitment venues to reach those at highest risk for HIV infection among HIV-negative men who have sex with men (MSM), given that some subgroups are difficult to reach, and venues vary in the demographic characteristics of the samples they yield. Compared to other venues, dating/hookup websites reached significantly higher-than-expected concentrations of White MSM aged 40 and above, including those who reported unprotected anal intercourse (UAI). Facebook was the most successful venue for the recruitment of MSM who used stimulants, including those who reported UAI. MSM who reported UAI were more likely to be recruited online. This study points to systematic variation in the samples obtained via different recruitment strategies, which should be taken into consideration when designing intervention/prevention programs targeting HIV-negative MSM.