BackgroundLow back pain (LBP) affects millions of people worldwide, and misconceptions about effective treatment options for this condition are very common. Websites sponsored by organizations recognized as trustworthy by the public, such as government agencies, hospitals, universities, professional associations, health care organizations and consumer organizations are an important source of health information for many people. However, the content of these websites regarding treatment recommendations for LBP has not been fully evaluated.ObjectiveThis study aimed to determine the credibility, accuracy, and comprehensiveness of treatment recommendations for LBP in noncommercial, freely accessible websites.MethodsWe conducted a systematic review of websites from government agencies, hospitals, universities, professional associations, health care organizations and consumer organizations. We conducted searches on Google. Treatment recommendations were coded based on the 2016 National Institute for Health and Care Excellence (NICE) guidelines and the 2017 American College of Physicians guideline on LBP. Primary outcomes were credibility of the website (4-item Journal of the American Medical Association benchmark), accuracy (proportion of website treatment recommendations that were appropriate), and comprehensiveness of website treatment recommendations (proportion of guideline treatment recommendations that were appropriately covered by a website).ResultsWe included 79 websites from 6 English-speaking countries. In terms of credibility, 31% (25/79) of the websites clearly disclosed that they had been updated after the publication of the NICE guidelines. Only 43.28% (487/1125) website treatment recommendations were judged as accurate. Comprehensiveness of treatment recommendations correctly covered by websites was very low across all types of LBP. For acute LBP, an average of 28% (4/14) guideline recommendations were correctly covered by websites. Websites for radicular LBP were the least comprehensive, correctly covering an average of 16% (2.3/14) recommendations.ConclusionsNoncommercial freely accessible websites demonstrated low credibility standards, provided mostly inaccurate information, and lacked comprehensiveness across all types of LBP.