Evaluation of readability and understandability of biotinidase deficiency information online

This study evaluates the readability and understandability of online resources on biotinidase deficiency, a metabolic disorder included in newborn screening programs. The aim is to determine whether these materials meet health literacy standards. Fifty online documents were initially identified via Google searches using "biotinidase deficiency." After excluding academic articles, duplicates, and inaccessible resources, 21 documents were analyzed. They were categorized as non-profit (hosted on domains such as .org, .gov, or .edu, representing public institutions and academic organizations)(13) or private (hosted on commercial domains like .com, often linked to medical facilities) (8) based on domain extensions. Readability was assessed using Readable.io, providing Flesch Reading Ease scores and Flesch-Kincaid Grade Level. The Patient Education Materials Assessment Tool (PEMAT) was used to evaluate understandability and actionability, with scores averaged by four reviewers. Statistical analyses compared group differences. Private articles showed markedly higher Flesch-Kincaid Grade Level scores, referring to higher reading difficulty, in contrast to non-profit articles (mean ± SD: 13.9 ± 2.2 vs. 10.7 ± 2.0; p = 0.002).There was no statistically significant difference in PEMAT understanding (U) scores between private and non-profit articles (mean ± SD: 52.0 ± 10.5 vs. 42.3 ± 11.4; p = 0.060) or actionability (A) scores (mean ± SD: 29.1 ± 20.0 vs. 13.4 ± 18.0; p = 0.063). Furthermore, articles classified as having lower readability levels (D and E) exhibited markedly reduced actionability scores compared to those with higher readability levels (A to C), indicating a correlation between text complexity and practical use. The recommended health literacy standards for biotinidase deficiency are not met by most online sources. In particular, materials that are difficult to read are less applicable and of limited benefit to parents or caregivers. Given that such readers are expected to take important actions such as conducting screenings or consulting healthcare professionals, the importance of making these materials more appropriate is significant. These findings highlight the importance of patient-centered, clear, and actionable health communication, particularly for conditions identified in newborn screening programmes.