National HIV Behavioral Surveillance System for Heterosexuals at Risk for HIV Infection- Implementation of Venue-Based Sampling in Baltimore, Maryland

National HIV Behavioral Surveillance (NHBS) was implemented by CDC in 2004 to monitor HIV-risk behaviors among three populations with disproportionate burden of HIV infection; namely, men who have sex with men (MSM), injection drug users (IDU), and heterosexuals (HET) living in areas highly impacted by HIV/AIDS and poverty. NHBS is implemented in alternating annual cycles recruiting each of the above populations. The current cycle, NHBS-HET, involves 25 metropolitan Statistical Areas (MSA), including Baltimore, Maryland (September 2006- October 2007). The Baltimore site is utilizing venue-based, time-space sampling (VBS). A lengthy period of formative research preceded participant recruitment and involved the following: a) mapping all census tracks in the MSA and ranking them in terms of highest HIV/AIDS prevalence and poverty; b) defining the high-risk area as the top 20% of these ranked census tracks; c) identifying venues frequented by heterosexuals in this high-risk area; d) enumerating venues to assess attendance patterns and feasibility of recruitment; e) creating the sampling frame of venues and venue-time periods to be used during recruitment of participants, and f) administering focus groups and interviews with community informants as to best practices for recruitment. Study implementation followed recruiting individuals in the high-risk area and had sex with an opposite-sex partner in the past year during randomly selected venue-time periods. Individuals were offered participation in a behavioral survey and HIV testing. Recruitment occurred at the venues using two mobile vans. NHBS-HET should provide information on prevalence of HIV and risk behaviors among heterosexuals in Baltimore.