Abstract
BACKGROUND: Monkeypox (Mpox) has become a Public Health Emergency of International Concern. Men who have sex with men (MSM) are the main population of Mpox infection. Vaccines are considered as the most effective methods for preventing and controlling Mpox epidemics. This study aimed at constructing a structural equation model (SEM) of the Mpox vaccination intention based on protection motivation theory (PMT) among MSM in China, so as to provide a strategic basis for relevant interventions. METHODS: A multi-center cross-sectional survey was conducted from November 2023 to March 2024 among 2481 MSM from six provinces (Shanghai, Guangdong, Xinjiang, Shaanxi, Yunnan, and Liaoning) in China. Participants completed a questionnaire evaluating PMT components, Mpox-related knowledge, risk perception, and vaccination intention. The SEM was constructed and evaluated whether it could effectively measure the protection motivation of MSM. RESULTS: A total of 2403 valid questionnaires were collected, with an effective rate of 96.86%. Most participants were young MSM, and 2,093 (87.1%) expressed high vaccination intention. The hypothetical SEM exhibited acceptable model fit, with the chi-square/degrees of freedom ratio (CMIN/DF) = 9.410, p < 0.001, root mean square error of approximation (RMSEA) = 0.059, goodness-of-fit index (GFI) = 0.911, comparative fit index (CFI) = 0.929, normed fit index (NFI) = 0.921, relative fit index (RFI) = 0.912, incremental fit index (IFI) = 0.929, and Tucker-Lewis index (TLI) = 0.920. The PMT constructs including maladaptive rewards, response efficacy, self-efficacy, and response costs were directly associated with vaccination intention and mediated the association between knowledge score, risk perception, and vaccination intention. The construct of maladaptive rewards was the strongest predictor. CONCLUSIONS: The majority of MSM had the intention to receive the Mpox vaccination. It is suggested that the vaccination program should focus on young MSM in response to the Mpox outbreak in the future. The PMT constructs can be applied to predict Mpox vaccination intention among MSM. Future Mpox vaccination promotion strategies can be based on the PMT constructs of maladaptive rewards, response efficacy, self-efficacy, and response costs to improve the Mpox vaccination intention of the MSM population.