Health and economic outcomes over 20 years with 4th-generation immunoassay.

All outcomes are relative to the status quo (approximately 1.18 million new infections over 20 years). MSM  =  men who have sex with men; IDU  =  injection drug user; 4G assay  =  fourth-generation antigen-antibody combination assay; AHI  =  acute HIV infection; NAAT  =  nucleic acid amplification test; QALY  =  quality-adjusted life year; ICER  =  incremental cost-effectiveness ratio compared to the status quo or next best strategy for each risk group. *  =  weakly dominated strategy (this strategy is not on the cost-effectiveness frontier and is thus not economically efficient).