National HIV Behavioral Surveillance System for Heterosexuals at Risk for HIV Infection Amy Lansky, Elizabeth DiNenno Behavioral Surveillance Team Behavioral and Clinical Surveillance Branch Division of HIV/AIDS Prevention, NCHHSTP, CDC Presented at APHA 135th Annual Meeting November 5, 2007 Washington DC The findings and conclusions in this presentation are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention
National HIV Behavioral Surveillance System (NHBS): Objective Among persons at high risk for HIV infections, assess: Prevalence of and trends in Risk behaviors HIV testing behaviors Assess exposure to and use of prevention services
Definition of Groups (inclusion criteria) Men who have sex with men (MSM) Man who had sex with 1 or more men in last 12 months Injection Drug Users (IDU) Injected drugs in last 12 months Heterosexuals at risk (HET) ?
Conceptual Framework Sexual Behaviors 2) Sexual Networks Risk behaviors that increase the likelihood of HIV infection 2) Sexual Networks Whether sex partners are infected 3) Social Context Demographic characteristics and social forces associated with population patterns of health and disease.
Conceptual Framework: Sexual Behaviors Multiple sex partners Concurrent partners Type of partner Condom use
Conceptual Framework: Sexual Networks What do people know about the risk behaviors of their sex partners?
Conceptual Framework: Social Context Demographic characteristics and social forces associated with population patterns of health and disease. High rates of disease Social forces
Social Context and Geography Many social forces and disparities are geographically concentrated Poverty Incarceration Racial segregation Geographic analysis (GIS) can be used to identify communities “at risk”
What data can you get in 25 cities? High Risk Areas What geographic unit makes sense for understanding social/sexual behaviors? Census tract: standardized population size What data can you get in 25 cities? High rates of heterosexually-acquired HIV/AIDS High rates of poverty
Geography and social interaction Physical connection to a high risk area Living there Socializing there Social connection Having sex partners/friends/family who live there
The NHBS-HET Pilot Cycle Definition: Heterosexual At Risk of HIV Infection Adult male or female aged 18-50 years Physical or Social Connection to a High Risk Area Had sex with an opposite-sex partner in the past 12 months
NHBS-HET Pilot Cycle Activities Mapping to identify High Risk Areas Formative research to learn about the local populations Survey and HIV testing with heterosexuals at risk
National HIV Behavioral Surveillance System (NHBS), 2006-2007 Seattle Boston Detroit New Haven Nassau New York City Newark San Francisco Chicago Philadelphia Denver Baltimore Las Vegas St. Louis Washington, DC Norfolk Los Angeles San Diego Atlanta Dallas Houston New Orleans Ft. Lauderdale Miami San Juan
NHBS Overall Strategy Conducted in rotating, annual cycles One group per cycle (MSM, IDU, HET) Different sampling methods each cycle Same populations and MSAs over time Consistent eligibility criteria 18+ years of age Resident of MSA Questionnaire Core + Local Questions Interviewer uses handheld computer
NHBS-HET Pilot Cycle: Sampling Methods Venue-based, Time-Space Sampling Time space sampling to randomly select venues. Participants in venues are systematically recruited and interviewed. Respondent-Driven Sampling Staff recruit “seeds” to start. Seeds recruit other IDU, those IDU recruit other IDU, etc. Sample size goal = 750 per MSA
NHBS-HET: Experiences from New Orleans, Baltimore, and Houston Mapping/identifying high risk areas Formative research methods & findings Sampling methods and results Venue based sampling Respondent driven sampling