Instrument-assessed quality features and clinical coverage of myocarditis videos on Bilibili and Douyin

Abstract Background Myocarditis is a clinically heterogeneous cardiovascular condition that may progress rapidly to severe outcomes, making early recognition and accurate public understanding essential. With the rapid expansion of short-video platforms, an increasing number of individuals rely on these media for cardiovascular health information; however, the quality and clinical reliability of such content remain uncertain. Objective: This study aimed to systematically assess the quality, reliability, and clinical relevance of myocarditis-related short videos on Bilibili and TikTok and to identify potential gaps in patient-oriented health communication. Methods: A cross-sectional content analysis was conducted on February 5, 2026. Videos were searched on Bilibili and TikTok using the Chinese term “心肌炎.” After screening, 253 eligible videos were included, comprising 121 from Bilibili and 132 from TikTok. Video characteristics, engagement metrics, uploader identity, video format, and thematic coverage were extracted. Quality and reliability were evaluated using the Global Quality Scale, JAMA benchmark criteria, modified DISCERN, Video Information and Quality Index, and Patient Education Materials Assessment Tool. Group comparisons and Spearman correlation analyses were performed. Results: Expert monologues were the most common video format, accounting for 51.0% of included videos. Quality-related scores differed significantly across video formats (P < 0.001). Course and literature-based videos achieved higher Global Quality Scale, Video Information and Quality Index, and JAMA scores, whereas expert monologues showed higher modified DISCERN scores. TikTok videos had higher modified DISCERN and JAMA scores and greater engagement, while Bilibili videos were longer and had higher understandability scores. Videos uploaded by medical professionals generally showed better quality and reliability than those uploaded by non-professionals. Engagement indicators were strongly correlated with each other but showed limited correlations with quality measures. Important content gaps were identified in prevention, complications, prognosis, and long-term recovery guidance. Conclusions: Myocarditis-related short videos on Bilibili and TikTok showed variable dissemination performance, but their overall quality, reliability, and educational completeness remained limited. High popularity did not necessarily indicate high informational value. Greater healthcare professional involvement, improved source transparency, and platform-tailored communication strategies are needed to improve myocarditis-related health information.