Content and educational quality of videos on ossification of the posterior longitudinal ligament across Bilibili, TikTok, and Kwai: a cross-sectional study

Abstract The educational value of online information about ossification of the posterior longitudinal ligament (OPLL) remains uncertain. We aimed to characterize and compare OPLL-related video content and educational quality across Bilibili, TikTok, and Kwai. On August 29, 2026, the first 100 results per platform were screened. Two researchers independently evaluated eligible videos using GQS, mDISCERN, JAMA, PEMAT-A/V, and a study-specific content checklist. Comparisons used nonparametric tests and Spearman correlations. Among 265 included videos (Bilibili, 68; TikTok, 99; Kwai, 98), 95.5% originated from professional healthcare sources. Median GQS, mDISCERN, JAMA, and OPLL-specific content scores were 3, 2, 2, and 8/15, respectively. Median understandability and actionability were 70.0% and 33.3%; 58.5% and 3.0% met the respective 70% thresholds. TikTok had the highest observed interaction counts and higher PEMAT scores than both comparators. Bilibili videos were longest and had lower JAMA scores; Kwai videos had been online longest. GQS did not differ across platforms. One high-volume tertiary spine center contributed 26.4% of videos, but excluding these videos did not materially alter the principal platform differences. Interaction-quality associations varied within platforms. These findings identify moderate educational quality but limited actionable guidance, supporting clearer sourcing and context-appropriate next steps without equating popularity with quality.