Quality of Health Information on the Internet for Urolithiasis on the Google Search Engine.

. To compare the quality of health information on the Internet for keywords related to urolithiasis, to assess for difference in information quality across four main Western languages, and to compare the source of sponsorship in these websites. . Health On the Net (HON) Foundation principles were utilised to determine quality information. Fifteen keywords related to urolithiasis were searched on the Google search engine. The first 150 websites were assessed against the HON principles and the source of sponsorship determined. . A total of 8986 websites were analysed. A proportion of HON-accredited websites for individual search terms range between 2.5% and 12.0%. The first 50 websites were more likely to be HON-positive compared to websites 51-100 and 101-150. French websites searched were more likely to be HON-positive whereas German websites were less likely to be HON-positive than English websites. There was no statistically significant difference between the rate of HON-positive English and Spanish websites. The three main website sponsors were from government/educational sources (40.2%), followed by commercial (29.9%) and physician/surgeon sources (18.6%). . Health information on most urolithiasis websites was not validated. Nearly one-third of websites in this study have commercial sponsorship. Doctors should recognise the need for more reliable health websites for their patients.