Assessment of Quality and Reliability of Short Videos on Photoelectric Anti-Aging on Bilibili and TikTok: A Cross-Sectional Study (Preprint)

<sec> <title>BACKGROUND</title> Photoelectric anti-aging technologies, as the core of non-invasive skin anti-aging, have become mainstream in aesthetic dermatology. Short-video platforms (Douyin and Bilibili) have gradually replaced traditional channels as the primary source of public information on this topic, but the uneven content quality (e.g., exaggerated efficacy, unapproved regimens, and missing safety information) and public cognitive gaps pose significant health risks. </sec> <sec> <title>OBJECTIVE</title> This study aimed to evaluate the quality and reliability of photoelectric anti-aging videos on Douyin and Bilibili using standardized tools, providing evidence for optimizing the information ecosystem. </sec> <sec> <title>METHODS</title> :A cross-sectional study was conducted. From August 31 to September 1, 2025, 150 initial videos were collected from each platform (logged-out state, comprehensive ranking), and 187 eligible videos (95 from Douyin, 92 from Bilibili) were screened via inclusion/exclusion criteria. Two dermatology residents extracted video characteristics (duration, engagement metrics) and uploader identities (dermatologists/medical institutions, science popularization bloggers, patients/general users), then assessed content quality using the Global Quality Score (GQS), modified DISCERN (mDISCERN), and Patient Education Materials Assessment Tool (PEMAT). Statistical analyses were performed with R 4.4.0 and SPSS 26.0 (Mann-Whitney U test, Kruskal-Wallis H test, Spearman correlation). </sec> <sec> <title>RESULTS</title> Bilibili had a longer median duration (441.5 vs. 116 seconds), higher GQS (median 3.0 vs. 2.0), and better PEMAT-U/A scores (all P&lt;0.05), while Douyin had higher median shares (1103.0 vs. 277.5, P&lt;0.05). Among uploader types: Dermatologists/medical institutions (45.99%) achieved the highest GQS/mDISCERN (median 3.0) and excelled in "indications" (0.65) and "mechanisms" (0.64) but lacked "post-treatment care" (0.17); patients/general users (22.99%) led in "post-treatment care" (0.44) but had poor "mechanisms" (0.19); science popularization bloggers (31.02%) showed balanced content and the best engagement but insufficient "risk coverage". Additionally, strong positive correlations existed between engagement metrics (ρ=0.85–0.91), but no correlation with quality scores. </sec> <sec> <title>CONCLUSIONS</title> This study reveals imbalances in "dissemination efficiency-professional depth" (Douyin vs. Bilibili) and "professionalism-practicality" (among uploaders), along with a disconnect between engagement and quality. Three-tiered strategies (platform supervision, uploader empowerment, public education) are needed to optimize the photoelectric anti-aging information environment and reduce health risks. </sec>