Effectiveness of vaping prevention campaign messages on cognitive and behaviorally proximal outcomes among adolescents and young adults: a systematic review and meta-analysis

Background Vaping among adolescents has decreased but remains common among young adults, with ongoing concerns about nicotine health risks. Public health campaigns have increased vaping prevention messages, but evidence on their effectiveness, especially on cognitive and behavioral outcomes, is limited. Objective This systematic review and meta-analysis aimed to synthesize recent experimental evidence on the effects of campaign-related vaping prevention messages on cognitive outcomes (e.g., knowledge, risk perception, perceived message effectiveness) and behaviorally proximal indicators (e.g., susceptibility to vaping and intentions to vape) among adolescents and young adults. Methods A systematic search of five databases (Cochrane, PubMed, Scopus, CINAHL, and Web of Science) was conducted through January 2025. Thirteen Randomized Controlled Trials (RCTs) met the inclusion criteria, with six eligible for meta-analysis. The review adhered to PRISMA guidelines and was registered in PROSPERO ( CRD42025643032). The risk of bias was assessed using the RoB 2.0 tool. Meta-analyses were performed using a random-effects model to estimate pooled effect sizes. Results The included studies (n=13) involved 11,235 participants aged 11–29 years. Most of the studies evaluated large-scale media campaigns or message-based interventions. Meta-analysis of six studies showed a statistically significant moderate effect on perceived vaping-related risk (Hedges’ g = 0.254; 95% CI: 0.187–0.321), with zero heterogeneity (I² = 0.0%). Due to the small number of studies, publication bias testing was exploratory. For behaviorally proximal outcomes, subgroup analyses revealed a statistically significant protective effect on vaping susceptibility (g = -0.166; 95% CI: -0.256 to -0.076; I² = 0.0%), while effects on intentions to vape were non-significant and heterogeneous (g = -0.089; I² = 62.3%). Narrative synthesis indicated consistent improvements in knowledge, attitudes, and perceived message effectiveness, particularly for messages emphasizing health harms and chemical exposure. Conclusion Campaign-related vaping prevention messages demonstrate consistent and robust effects on cognitive outcomes and susceptibility to vape, but yield heterogeneous and context-dependent effects on intentions. These findings underscore the importance of strategic message design and thematic framing while highlighting the need for longitudinal and population-level studies to determine whether cognitive shifts translate into sustained behavioral change. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD42025643032 , identifier CRD42025643032.