Effects of a web-based HPV vaccination intervention on cognitive outcomes among young gay, bisexual, and other men who have sex with men.

Knowledge, attitudes, and beliefs are important antecedents to HPV vaccination, yet remain suboptimal among young gay, bisexual, and other men who have sex with men (YGBMSM). We report the effects of a theoretically-informed, web-based HPV vaccination intervention on these cognitive outcomes. From 2019-2021, we recruited a national sample of YGBMSM ages 18-25 in the United States who were unvaccinated against HPV ( = 1,227). Participants received either standard HPV vaccination information online (control) or population-targeted, individually-tailored content online ( intervention). Mixed effects models determined if pre-post changes in cognitive outcomes differed between study groups. For five of seven knowledge items about HPV, there were larger pre-post increases among the intervention group than the control group in the percentage of participants who provided correct responses (all statistically significant at  = .05 after Holm's correction). There were also larger pre-post improvements among the intervention group than the control group for most attitudes and beliefs examined, including response efficacy of HPV vaccine (pre-post increases in means: 0.57 vs. 0.38); self-efficacy for the HPV vaccination process (pre-post increases in means: 0.23 vs. 0.10); and intention to get HPV vaccine (pre-post increases in means: 0.70 vs. 0.28) (all statistically significant at  = .05 after Holm's correction). is a promising tool for improving key cognitive antecedents to HPV vaccination among YGBMSM, supporting the use of theoretically-informed interventions to affect such outcomes. If efficacious in increasing HPV vaccine uptake in future analyses, this intervention could be utilized in clinical and other healthcare settings that provide services to YGBMSM.