<p>BASEDE_1.</p>

Three optometrists independently assessed the videos via the modified DISCERN (mDISCERN), the Journal of the American Medical Association (JAMA) benchmarks, and the Global Quality Score (GQS). Interobserver reliability was evaluated using two-way mixed-effects intraclass correlation coefficients (ICC) with absolute agreement. Quantitative engagement metrics (views, likes, dislikes, the view ratio, and the video power index (VPI) were also recorded.

Non-parametric tests were used for subgroup comparisons by language, topic, source, and presenter gender, with Bonferroni adjustments applied for multiple comparisons.</p> <p>Results</p><p>Among the 235 videos analysed, 52.8% were in English, and 47.2% were in Spanish. Overall video quality and reliability were highly variable. Interobserver reliability across the entire dataset was good for GQS (ICC = 0.832) and mDISCERN (ICC = 0.750), but poor for JAMA (ICC = 0.447).

Good interevaluator agreement was maintained across all tools for Spanish videos (ICC range: 0.701–0.803), whereas English videos showed lower agreement for mDISCERN (ICC = 0.768) and JAMA (ICC = 0.536), but excellent agreement for GQS (ICC = 0.849). Spanish-language videos scored significantly higher on mDISCERN (P = 0.026), while JAMA and GQS scores showed no significant differences between languages after adjusting for multiple comparisons.

Videos from universities or professional organisations were of higher quality and reliability but constituted a minority of the sample. The presenter’s gender did not impact quality or engagement. English-language videos had higher view ratios and VPI values, indicating greater visibility, although not necessarily higher scientific quality.</p> <p>Conclusions</p><p>YouTube provides a wide range of content on pediatric myopia control, but its overall quality, realiability and scientific alignment are inconsistent.

The use of standardized evaluation tools reveals significant differences in subjective assessment depending on the scoring instrument and video language. The increased participation of healthcare professionals in creating evidence-based videos is needed to increase public health literacy.</p></div>