Attitudes toward driving after cannabis use: A systematic review and meta-analysis

As cannabis policies become more permissive, there is concern that driving after cannabis use (DACU) will increase. From a prevention perspective, understanding whether attitudes toward DACU are positive or negative can guide messaging to reduce DACU. This meta-analysis summarizes quantitative data on attitudes toward DACU safety. Four electronic databases were searched from their inception to February 2024 for studies reporting quantitative data on attitudes toward cannabis use and driving. A total of 1,099 records were retrieved. We summarized data from studies reporting the proportion of respondents endorsing a response option(s) and studies reporting means and standard deviations of endorsed Likert-scale response options using inverse-variance methods. Most respondents had unfavorable views on DACU safety. Among 32 studies, the pooled proportion of respondents endorsing negative attitudes toward DACU was 0.69 (95% CI: 0.62; 0.75). Only ten studies reported the mean and standard deviation of Likertscale responses; attitudes in these studies were in line with results from the analysis of proportions. Although most people have negative attitudes toward DACU, it is concerning that around one third do not. Prevention initiatives can capitalize on the association between attitude and behaviour to design public messaging.