Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University School of Public Health, Providence, RI, USA.
Department of Health Education and Behavior, University of Florida, Gainesville, FL, USA.
J Exp Anal Behav. 2024 Mar;121(2):233-245. doi: 10.1002/jeab.905. Epub 2024 Feb 14.
Preexposure prophylaxis (PrEP) prevents human immunodeficiency virus (HIV) but not other sexually transmitted infections (STIs). Men who have sex with men (MSM) who take PrEP tend to report reduced condom use, but little is known about the underlying mechanisms. For this study, MSM who take PrEP (i.e., PrEP experienced; n = 88) and MSM who do not (i.e., PrEP naïve; n = 113) completed an online study, including the condom purchase task (CoPT). The CoPT assesses decisions to purchase condoms across escalating prices (range: free-$55) for sex with different types of hypothetical partners: those least likely to have an STD (least STD) and those that participants most want to have sex with (most want sex with). When condoms were free, PrEP-experienced MSM had a lower rate of condom purchasing than did PrEP-naïve MSM. For both partner types, PrEP-experienced MSM reached a price break point (i.e., would not buy condoms) at a lower price than did PrEP-naïve pariticipants. For the most-want-sex-with partner at the price at which participants elected not to buy condoms, only 23% of PrEP-experienced MSM chose to abstain from sex when not purchasing condoms versus 53% among PrEP-naïve MSM. Similar patterns were observed for the least-STD partner. The results support the potential utility of the CoPT in identifying behavioral mechanisms related to condom use and PrEP.
暴露前预防（PrEP）可预防人类免疫缺陷病毒（HIV），但不能预防其他性传播感染（STI）。服用 PrEP 的男男性行为者（MSM）往往报告减少使用安全套，但对潜在机制知之甚少。在这项研究中，服用 PrEP 的 MSM（即 PrEP 经验者；n=88）和未服用 PrEP 的 MSM（即 PrEP 未经验者；n=113）完成了一项在线研究，包括 condom purchase task（CoPT）。CoPT 通过不同价格（免费到 55 美元）评估参与者与不同类型的假想伴侣发生性行为时购买安全套的决策：那些最不可能患有 STD（STD 可能性最低）和那些参与者最想与之发生性行为的人（最想与性发生）。当安全套免费时，PrEP 经验者购买安全套的比率低于 PrEP 未经验者。对于这两种类型的伴侣，PrEP 经验者在低于 PrEP 未经验者的价格下达到价格突破点（即不会购买安全套）。对于最想与性发生的伴侣，在参与者选择不购买安全套的价格下，只有 23%的 PrEP 经验者选择在不购买安全套时避免性行为，而 PrEP 未经验者中这一比例为 53%。对于 STD 可能性最低的伴侣，也观察到类似的模式。这些结果支持 CoPT 在识别与安全套使用和 PrEP 相关的行为机制方面的潜在效用。
