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




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


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.

Author Biographies

Saeideh Valizadeh-Haghi, Department of Medical Library and Information Sciences, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran

Saeideh Valizadeh-Haghi, PhD (health information management), works as assistant professor in the Department of Medical Library and Information Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Her research interests include e-health literacy, health website quality assessment, Internet-related researches, health information management, mobile health, and ubiquitous technology in health care (UHealth).

Yasser Khazaal, Department of Psychiatry, Lausanne University Hospitals and Lausanne University, Lausanne

Yasser Khazaal, MD, is member of the Board of Addiction Medicine, Department of Psychiatry, Lausanne University Hospital. He is vice-president of the Swiss Society of Social Psychiatry, president of the Swiss Society of Cognitive Psychotherapy. Professor Khazaal is involved in a number of studies related to e-health, anxiety, and projects related to the development and assessment of games or computer-based treatments for different mental health disorders. He is also interested in the promotion of new models of patient care aiming to promote empowerment and recovery.

Shahabedin Rahmatizadeh, Department of Health Information Technology and Management, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran

Shahabedin Rahmatizadeh, PhD (medical informatics), works as assistant professor in Shahid Beheshti University of Medical Sciences, Tehran, Iran. His research interests include quality evaluation of health websites from different aspects, e-health literacy, ubiquitous technology in health care (UHealth), and management information systems (MIS) usability evaluation.


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Original Investigation