The PRS efficacy reviews, which are conducted to identify evidence-based HIV behavioral interventions, are divided into two chapters: Risk Reduction (RR) Efficacy Review and Medication Adherence (MA) Efficacy Review. The efficacy review process uses standard systematic procedures for searching and reviewing the intervention research literature, but a separate customized search strategy for each of the two reviews. Both begin with a comprehensive search of the literature to identify evaluations of HIV behavioral interventions. Each evaluation report is then reviewed using criteria explicit to the review to determine which interventions have been rigorously evaluated and have demonstrated efficacy in reducing HIV or STD incidence, in reducing HIV-related risk behaviors, or increasing HIV-protective behaviors for the RR review, or in reducing HIV viral load or improving HIV medication adherence behaviors for the MA review. More detailed information regarding the efficacy review methods and criteria for the two separate reviews can be found below.