The Impact of Short-Form Video and Optimistic Bias on Engagement in Oral Health Prevention: Integrating a KAP Model.

College students are recognized as a demographic particularly susceptible to higher oral health risks due to irregular and unhealthy habits. While previous research has underscored these risks through descriptive studies within this group, a significant gap persists in the literature regarding the impact of contemporary media, specifically oral-health-related content, on the engagement in oral health prevention among Chinese college students. To address this gap, this study, guided by the extended knowledge-attitude-practice (KAP) theory model, explores the direct, mediated, and serially mediated mechanisms through which exposure to oral health short-form videos on Douyin influences their participation in oral health prevention. An empirical cross-sectional online survey was conducted, with valid data (N = 421) analyzed using descriptive statistics and hierarchical regression. Mediation and serial mediation analyses were also performed using SPSS version 25.0. The analysis revealed that exposure to oral health short-form videos had a positive direct effect on both oral health knowledge and the reduction of optimistic bias among Chinese college students. Furthermore, a significant serial mediation effect of oral health knowledge and oral health attitude was identified. The findings underscore the substantial applicability and explanatory power of the extended KAP theory model in understanding engagement in oral health prevention.