Perceived message effectiveness and readiness to quit among youth in Guangdong: The mediating role of self-efficacy and the moderating effect of nicotine dependence.

Tobacco use among adolescents in China poses a serious public health challenge, with Guangdong being a key region for intervention. Understanding the psychological mechanisms of perceived message effectiveness (PME) can inform more effective tobacco control strategies. This study aimed to examine how PME influences quitting readiness among youth smokers in Guangdong, with self-efficacy as a mediator and nicotine dependence as a moderator. A cross-sectional survey was conducted among youth smokers recruited from schools and community centers in Guangdong between August and September 2025, using self-administered questionnaires. PME was assessed using a standardized short scale that evaluates the perceived persuasiveness of anti-smoking messages. Participants aged 15 to 24 years were selected using stratified cluster sampling from secondary schools, vocational colleges, and community centers across Guangdong province. Participants completed validated measures, including the Hooked on Nicotine Checklist, the Smoking Self-Efficacy Questionnaire-12, and the Readiness/Contemplation Ladder. Correlation, mediation, moderation, and moderated mediation analyses were performed using SPSS version 26.0 and the PROCESS macro with bootstrapping. PME was positively correlated with both self-efficacy (r = 0.42, P < .001) and readiness to quit (r = 0.36, P < .001), indicating moderate associations consistent with behavioral research expectations. Mediation analyses indicated that self-efficacy significantly mediated the PME-readiness relationship (indirect standardized effect β = 0.20, 95% confidence interval [0.11, 0.30]), accounting for approximately 55% of the total effect. Nicotine dependence moderated both the PME-self-efficacy (interaction β = -0.12, P = .015) and the self-efficacy-readiness pathways (interaction β = -0.14, P = .018). The indirect effect of PME on readiness was significant among low-dependence youth but not among highly dependent youth. PME promotes quitting readiness mainly through self-efficacy, but this pathway is weakened among youth with higher nicotine dependence. Tailored health communication strategies should therefore combine efficacy-building messages with additional support for highly dependent smokers. The findings suggest that public health campaigns aiming to increase quitting readiness among youth should focus on improving the perceived persuasiveness of anti-smoking messages and strengthening self-efficacy, particularly by providing extra support for those with higher nicotine dependence.