Department of Health Communication, School of Public Health, The University of Tokyo
Background: Cancer screening rates are lower in Japan than those in western countries. Health professionals publish pro-cancer screening messages on the internet to encourage audiences to undergo cancer screening. However, the information provided is often difficult to read for lay persons. Further, anti-cancer screening activists warn against cancer screening with messages on the Internet. We aimed to assess and compare the readability of pro- and anti-cancer screening online messages in Japan using a measure of readability. Methods: We conducted web searches at the beginning of September 2016 using two major Japanese search engines (Google.jp and Yahoo!.jp). The included websites were classified as "anti", "pro", or "neutral" depending on the claims, and "health professional" or "non-health professional" depending on the writers. Readability was determined using a validated measure of Japanese readability. Statistical analysis was conducted using two-way ANOVA. Results: In the total 159 websites analyzed, anti-cancer screening online messages were generally easier to read than pro-cancer screening online messages, Messages written by health professionals were more difficult to read than those written by non-health professionals. Claim × writer interaction was not significant. Conclusion: When health professionals prepare pro-cancer screening materials for publication online, we recommend they check for readability using readability assessment tools and improve text for easy comprehension when necessary.