HIV/AIDS surveillance in the United States, 1981-2001.

We review the HIV/AIDS reporting system, including the legal basis for reporting, the methods and infrastructure for reporting, evaluation of the completeness and quality of the data, and analysis and dissemination of reports. Other information systems (e.g., seroprevalence surveys and behavioral surveys) that collect useful information for HIV prevention and care programs are also described. Multiple data collections systems are needed to monitor the HIV/AIDS epidemic in the United States and to collect the information needed to plan, implement, and evaluate prevention and care programs.