Quality and readability of Persian-language online information on oral lichen planus: a cross-sectional content analysis

Patients with oral lichen planus (OLP) increasingly use the internet to obtain information about their condition, treatment, and prognosis. However, the quality and readability of Persian-language online information on OLP have not been comprehensively evaluated. This study assessed the quality, transparency, and readability of Persian-language web-based information on OLP and examined associations between search ranking and information quality. A cross-sectional content analysis was conducted. The final web search was performed on 21 October 2024. Three Persian OLP-related search terms were independently searched in Google, Bing, and Yahoo!, and the first 100 results from each search were screened. After removal of duplicate URLs and application of predefined eligibility criteria, 118 webpages were included. Information quality was assessed using the DISCERN instrument, while transparency was evaluated using the four Journal of the American Medical Association (JAMA) benchmarks. Readability was assessed using the Flesch Reading Ease Score (FRES), Flesch–Kincaid Grade Level (FKGL), Flesch–Kincaid Age Level (FKAL), and Gunning Fog Grade Level (GFG). Sentence, word, and syllable counts were performed manually using a standardized procedure. Pearson’s and Spearman’s correlation coefficients were used to assess associations between search ranking and information quality. Group comparisons were performed using independent-samples t -tests or Mann–Whitney U tests, as appropriate. Effect sizes and confidence intervals were reported, and a Benjamini–Hochberg false discovery rate (FDR) sensitivity analysis was performed to account for multiple comparisons. The mean overall DISCERN score was 2.90 ± 0.54, indicating suboptimal information quality, while the mean JAMA benchmark score was 1.63. The mean FRES, FKGL, FKAL, and GFG scores were 8.62 ± 1.72, 15.01 ± 0.66, 20.00 ± 0.66 years, and 10.14 ± 1.24, respectively, indicating substantial reading difficulty. Search ranking was negatively associated with DISCERN scores (Pearson r = − 0.352, P < 0.001; Spearman r s = − 0.465, P < 0.001), but not with JAMA scores ( r s = − 0.107, P = 0.249). DISCERN and JAMA scores were not significantly correlated ( r s = 0.086, P = 0.357). Non-profit webpages had higher DISCERN scores than commercial webpages (3.09 ± 0.49 vs. 2.85 ± 0.55; P = 0.031; Cohen’s d = 0.46), whereas commercial webpages had higher JAMA benchmark scores (1.81 ± 0.98 vs. 1.04 ± 1.02; P < 0.001; rank-biserial correlation = − 0.44). After FDR adjustment, the associations between search ranking and DISCERN score and between website type and JAMA score remained statistically significant, whereas the difference in DISCERN scores between commercial and non-profit webpages was borderline. Persian-language web-based information on OLP was generally of limited quality and difficult to read. Search ranking was not consistently associated with information quality, and the two assessment instruments showed no consistent association in the evaluated webpages. The findings highlight opportunities to improve the quality, transparency, and readability of Persian-language digital health information, while further research is needed to determine whether such improvements translate into better patient comprehension and informed decision-making.