Health websites on COVID-19: are they readable and credible enough to help public self-care?

Saeideh Valizadeh-Haghi, Yasser Khazaal, Shahabedin Rahmatizadeh


Objective: There are concerns about nonscientific and/or unclear information on the coronavirus disease 2019 (COVID-19) that is available on the Internet. Furthermore, people’s ability to understand health information varies and depends on their skills in reading and interpreting information. This study aims to evaluate the readability and creditability of websites with COVID-19-related information.

Methods: The search terms “coronavirus,” “COVID,” and “COVID-19” were input into Google. The websites of the first thirty results for each search term were evaluated in terms of their credibility and readability using the Health On the Net Foundation code of conduct (HONcode) and Flesch-Kincaid Grade Level (FKGL), Simple Measure of Gobbledygook (SMOG), Gunning Fog, and Flesch Reading Ease Score (FRE) scales, respectively.

Results: The readability of COVID-19-related health information on websites was suitable for high school graduates or college students and, thus, was far above the recommended readability level. Most websites that were examined (87.2%) had not been officially certified by HONcode. There was no significant difference in the readability scores of websites with and without HONcode certification.

Conclusion: These results suggest that organizations should improve the readability of their websites and provide information that more people can understand. This could lead to greater health literacy, less health anxiety, and the provision of better preventive information about the disease.


Coronavirus; Comprehension; Anxiety; Cyberchondria; Patient Portals; Public Health Informatics; Medical Informatics; Health Education; Internet-Based Intervention

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