Evaluating fluoride-related YouTube videos in Japan: A comparative analysis of understandability, actionability, and reliability between pro- and anti-fluoride content

This study aimed to compare pro- and anti-fluoride Japanese YouTube videos on understandability, actionability, flow, reliability, and engagement. Eighty-four videos found via a keyword search (pro = 49, anti = 18, other = 17) were analyzed. Quality was assessed using three validated tools—namely, Patient Education Materials Assessment Tool for Audiovisual Materials (PEMAT-A/V), Global Quality Score (GQS), and modified DISCERN (mDISCERN). Engagement was measured as view rate. Pro-fluoride videos scored higher on reliability (mDISCERN 2.6 ± 1.0 vs 1.3 ± 0.6) and overall quality (GQS 2.5 ± 1.4 vs 1.0 ± 0.9; both p < 0.001). No group differences emerged for understandability (58% versus 53%; p = 0.23) or actionability (60% versus 53%; p = 0.33). In the anti-fluoride group, a higher view rate positively correlated with understandability and GQS (ρ ≈ 0.53; p ≈ 0.03); no correlation was found for pro-videos. Only 27% of the videos satisfied the PEMAT-A/V understandability threshold. Reliable, expert-made pro-fluoride videos attract modest audiences, whereas anti-fluoride videos can achieve a wide reach when they are easy to follow and well-structured. However, scientific accuracy alone cannot guarantee audience reach or engagement. Oral health authorities should design algorithm-sensitive, evidence-based videos that are clear and actionable. This is the first study to integrate the PEMAT-A/V, GQS, and mDISCERN with YouTube analytics for Japanese fluoride content, thereby providing a data-driven framework for algorithm-aware oral-health messaging. • Pro-fluoride videos exhibited a higher reliability score but lower audience reach. • Understandable and well-structured anti-fluoride videos exhibited a high view rate. • Only one-quarter of all videos satisfied the PEMAT-A/V understandability threshold. • PEMAT-A/V, GQS, and mDISCERN triangulated with analytics reveal engagement drivers.