Textual and pictorial enhancement of cannabis warning labels: An Online experiment among at-risk U.S. young adults

Abstract

BackgroundThis study experimentally examines whether enhanced cannabis warning labels (CWLs) outperform those currently required in the U.S. in improving recall of health risks, emotional responses, and perceived message effectiveness among at-risk young adults. MethodWe conducted an online national survey-based experiment in October 2020. Young adults aged 18–26 years old and at-risk for cannabis use (N = 523) were randomly assigned in an online experiment, to view either currently required CWLs in California with small font and a composite health risk statement, or enhanced single-theme CWLs with varying textual and pictorial components. We performed linear regression analyses to compare the enhanced with existing CWLs on information recall, negative emotions, and perceived message effectiveness. Furthermore, information recall and negative emotions were examined as parallel mediators to better understand the mechanisms underlying effective textual and pictorial enhancement of CWLs. ResultsCompared with currently required CWLs in California, both textually (b = 0.30, p = .011) and pictorially (b = 0.59, p < .001) enhanced CWLs increased recall accuracy. Pictorially enhanced CWLs outperformed their text-only counterparts (b = 0.28, p = .019) in improving information recall. Only pictorially enhanced CWLs improved perceived message effectiveness (b = 0.31, p = .008), which was mediated by negative emotions but not by information recall. ConclusionsGiven rapid expansion of the cannabis industry and declining perception of harm, currently required CWLs in the U.S. such as California’s, would benefit from redesign to improve public understanding of health risks and to prevent youth use.