A comparative study of medical information quality and dissemination efficacy of knee arthroplasty videos in Bilibili/TikTok short video platforms

Objective: This study aims to systematically assess the content characteristics and information quality of knee arthroplasty-related videos on TikTok and Bilibili, in order to provide evidence to support the optimization of health science communication. Methods: On February 13, 2025, we searched for "" (knee arthroplasty in Chinese) on TikTok and Bilibili, and initially collected 100 videos from each platform according to the default sorting order, which were then subjected to further screening. Videos containing irrelevant content, lacking audio, being non-original reposts, or intended for advertising and marketing purposes were excluded. The quality and reliability of the included videos were assessed by applying four validated instruments: the modified version of DISCERN (mDISCERN), the Global Quality Score (GQS), the Video Information and Quality Index (VIQI), and the Patient Education Materials Assessment Tool (PEMAT). Interplatform variations and correlations between quality and user interactions were analyzed via Mann‒Whitney U and chi-square tests. Results: A total of 162 knee arthroplasty related videos were analyzed, including 88 from TikTok and 74 from Bilibili. TikTok videos demonstrated higher engagement and more certified uploaders, whereas Bilibili featured more diverse professional backgrounds. Bilibili emphasizing anatomy using PPT/class based, animation/ motion and television program/documentary styles. TikTok focusing on examination/diagnosis, and treatment delivered through solo narrative and Questions and Answers (Q&A). TikTok videos achieved higher scores across all quality assessment tools. Professionally generated content consistently outperformed nonprofessional content across most quality metrics, whereas no significant difference was observed for mDISCERN. Correlation analysis showed that engagement was strongly associated with VIQI on both platforms, with additional moderate associations for GQS and PEMAT only on TikTok, while mDISCERN showed no significant correlation. Conclusions: TikTok favors high user engagement, whereas Bilibili provides more structured educational content. Professional involvement is essential to ensure information quality and effective medical communication.