LAUSR

We performed a cross-sectional study of internet claims focused on the health benefits of cannabis use. We extracted information on claims from two different sources on June 15, 2019: (1) We searched Google for “marijuana benefits,” “weed benefits,” and “marijuana health.”Our sample includes the top ten lay webpages from each Google search. (2) We searched Buzzsumo, a social media analyzer tool that calculates online engagement with news articles, to measure each article’s engagement by its number of likes, shares, and comments on social media sites. We used the terms: “marijuana benefits OR cannabis benefits OR weed benefits,” and “marijuana health,” restricting our search to articles published in the previous 2 years (2017–2019). We excluded articles irrelevant to the potential health benefits of cannabis use, and only included high-impact articles (over 10,000 engagements) because they had the most reach with an online audience. Internet links to the scientific literature were not included since the focus of this analysis was to characterize information available to the public in the lay press. Two reviewers (NL, MG) independently reviewed webpages and articles to extract and categorize claims about the health benefits of cannabis use and tally the frequency of each claim category. Two investigators with expertise in cannabis evidence review (SK, DK) evaluated the literature published before November 2019 to determine claim validity based on available evidence. The two investigators searched Medline to first identify published systematic reviews. For claims with no relevant systematic reviews, randomized controlled trials were sought. Health claims were compared to the existing trial evidence and categorized as not true, partly true, and true. Disagreements were resolved by discussion.