Disparities between English and Spanish in readability of online endodontic information for laypeople

Abstract Background In this study, the authors assessed the readability of online endodontic information in English and Spanish. Methods The authors performed a systematic search in Google in May 2016. Search queries were “root canal treatment” and “?Que es una endodoncia?” without limits or filters. The authors assessed English readability by using Flesch-Kincaid Reading Grade Level, Flesch Reading Ease Score, Gunning Fog Index, Coleman-Liau index, automated readability index, and Simple Measure of Gobbledygook (SMOG) index. The authors calculated readability for Spanish by using the Fernandez-Huerta index and INFLESZ (Ines-Barrio). Results The authors assessed the first 100 consecutive sites identified with each search strategy and selected 117 sites. Readability scores for English-language sites were in the category of normal to read, easily understood by 13- through 15-year-old students (Flesch Reading Ease Score, 63, interquartile range (IQR) [53.9-66.2]; Gunning Fog Index, 10.4, IQR [8.8-12]; Coleman-Liau index, 12.5, IQR [11.6-13.3]; and automated readability index, 8.6, IQR [6.7-9.8]). SMOG results led to the estimation that only 7 years of education would be needed to understand these contents (SMOG, 7.6, IQR [6.5-8.8]). Spanish-language sites had a readability index normal for an adult, equivalent to a seventh or eighth school year (Fernandez-Huerta, 62.3, IQR [59.7-66.6]; INFLESZ, 57.5, IQR [55.1-62.1]). The authors found that 36.6% of English-language sites had some degree of difficulty for readers to understand their contents, whereas 23% of Spanish-language sites had some degree of difficulty (14.46; 95% confidence interval, −3.16 to 30.08). Conclusions Spanish- and English-language electronic health information about endodontic treatment is acceptable to read, but—particularly for English-language sites—there is an important proportion of sites scoring difficulty levels well above the recommendations. Practical Implications The internet is a useful tool for communicating with patients, but available endodontic information is difficult for laypeople to understand. Endodontists should produce relevant materials in plain language to overcome this problem.