Abstract
BACKGROUND: Vaccine hesitancy is a significant barrier to achieving high vaccination rates, particularly among men who have sex with men (MSM), a group at increased risk for Mpox. This study aimed to develop and validate a Mpox vaccine hesitancy scale specifically tailored for Chinese MSM, grounded in the protection motivation theory (PMT). METHODS: An online survey through snowball sampling was conducted from October 2023 to March 2024, collecting 2403 valid responses across six representative regions in China. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted to evaluate the scale's construct validity, while reliability was assessed using Cronbach's α coefficient. The predictive validity of the scale was analyzed using Receiver Operating Characteristic (ROC) analysis. RESULTS: EFA ultimately retained 22 items in the Mpox vaccination scale and identified four distinct dimensions: Maladaptive Rewards (seven items), Self-efficacy (seven items), Response Efficacy (four items), and Response Costs (four items). These dimensions were confirmed by CFA, which demonstrated satisfactory model fit indices (χ²/df = 4.382, RMSEA = 0.053, SRMR = 0.048, GFI = 0.935, CFI = 0.967, NFI = 0.958, TLI = 0.963, and IFI =0.967). All indices were within acceptable ranges. The scale exhibited good internal consistency, with a Cronbach's alpha of 0.906, and strong content validity, with an S-CVI/Ave of 0.952. The scale's predictive accuracy was evaluated using Receiver Operating Characteristic (ROC) analysis. When used to evaluate the scale's predictive accuracy, it yielded an area under the curve (AUC) of 0.854 after adjustments, indicating good predictive ability between high and low hesitancy. CONCLUSIONS: This scale provides a reliable and valid tool for assessing Mpox vaccine hesitancy among MSM and can be used to gauge Mpox vaccination intention within this group.