Quantitative Methods Used to Evaluate Impact of Combination HIV Prevention Intervention: A Methodological Systematic Review.

Combination HIV prevention aims to provide the right mix of biomedical, behavioral and structural interventions, and is considered the best approach to curb the HIV pandemic. The impact evaluation of combined HIV prevention intervention (CHPI) provides critical information for decision making. We conducted a systematic review of the literature to map the designs and methods used in these studies. We searched original articles indexed in Web of Science, Scopus and PubMed. Fifty-eight studies assessing the impact of CHPI on HIV transmission were included. Most of the studies took place in Asia or sub-Saharan Africa and were published from 2000 onward. We identified 36 (62.1%) quasi-experimental studies (posttest, pretest-posttest and nonequivalent group designs) and 22 (37.9%) experimental studies (randomized designs). The findings suggest that diverse methods are already rooted in CHPI impact evaluation practices as recommended but should be better reported. CHPI impact evaluation would benefit from more comprehensive approaches.