Estimating HIV/AIDS incidence: Adjusting case reports for changes in definition

The purpose of this paper is to assess different procedures used in the modeling of the AIDS epidemic that account for changes in the definition of AIDS. Specifically, we assess three methods that adjust for the effect of definition changes on the modeling of HIV reconstructions. Our results suggest that how we account for definition changes is a critical influence on the severity and the shape of the estimated HIV/AIDS epidemic. Also, the scope of the recent (1993) definition change is sufficiently broad to limit approaches based on adjusting to a single, consistent definition. The most realistic approach appears to be one based on a dynamic disease progression model that accounts for AIDS definition changes via changes in disease incubation.