“…Although most of the studies defined sexual risk behavior as sex without a condom, specification of the measure was highly variable. Some of the studies analyzed by partner type (i.e., primary or casual partner) or only analyzed a specific partner type [25,32,54], including sexual behavior with a casual partner [10,28,33,39]. Another difference across studies was subanalysis by insertive or receptive anal sex [26,29,38,54], HIV-discordance or concordance between the respondent and his partner [29,37,40,41,52,55,56], and single vs. multiple partners during the sexual event [31].…”