Serving as a complement to the ongoing HIV seroprevalence studies in methadone treatment centers, the Record-Based Incidence Study (RBIS) was initiated in 1994 to track, prospectively, the course of the HIV epidemic among a population considered at high risk for HIV infection. Data collected through conduct of the RBIS have proven vital in terms of monitoring emerging trends among injection drug users in Los Angeles County. Because seroprevalence data are limited in projecting the future course of the HIV epidemic, HIV incidence data are of particular importance for planning the allocation of scarce resources as well as the timely development of prevention programs that specifically target those at greatest risk of acquiring or transmitting HIV.
- To develop standard procedures for conducting record-based HIV seroincidence surveys in methadone treatment center populations.
- To estimate the incidence of HIV in individuals who have received multiple HIV tests during the course of their methadone treatment.
- To assess risk behaviors associated with HIV seroconversion among patients attending methadone treatment centers in Los Angeles County.
- To monitor trends in HIV seroincidence among patients attending methadone treatment centers in Los Angeles County.
RBIS is a prospective, record-based cohort study conducted in accordance with the CDC Protocol Guidelines for Estimating HIV Seroincidence in Among Illicit Drug Users, July 1994. Each methadone treatment client visiting any of the three participating clinics (West County Medical Clinic, Narcotics Prevention Project, or Western Pacific Panorama Medical Clinic) is offered confidential HIV counseling and testing. Clients who accept a confidential test complete an interviewer-administered, demographic and risk behavior survey. All methadone treatment clients accepting a confidential HIV test at the three participating clinics will be entered into a passive cohort and the clinic records will be monitored daily for repeat confidential HIV test visits. Incident HIV infections will be detected when a client receives more than one confidential HIV test as a result of repeat HIV tests during the course of the client's methadone treatment. Incident infections will be defined as a positive HIV antibody test result preceded by at least one negative HIV test result. HIV test results are linked to interviewer-administered, demographic and risk behavior survey through use of an unique ID number common to all forms.
Mark Weber, Ph.D.
Bill Reidy, M.H.A.