Assessing the Prevalence of Cannabis Use Through a Survey About Criminal Activity Versus One About Alcohol, Tobacco, and Other Drugs

Abstract

Background: The prevalence of cannabis use in the United Kingdom might be underestimated using the Crime Survey of England and Wales. The current study examined whether responding to questions about their cannabis use as part of a crime survey would be less likely to report that they use cannabis compared to those responding to the same questions that are part of a survey about health. Methods: Participants were randomized to be told that the items about cannabis use came from a crime survey versus from a health survey. In addition, the sample was recruited using a representative online sampling method and compared to published rates of self-reported cannabis use collected as part of the Crime Survey for England and Wales. Results: There was no significant difference (p > 0.05) in the proportion endorsing cannabis use between those told the items came from a crime survey versus a health survey. However, self-reported rates of cannabis use collected as part of the online panel (51.3% ever use; 11.9% past year; age range 18–64 years) appeared higher than those reported based on results from the Crime Survey for England and Wales (37.2% ever and 5.8% past year; age range 18–59 years). Conclusion: The current study did not find evidence that manipulating whether participants were told that the items asking about cannabis use came from a survey asking about criminal activity versus one about health had an impact on self-reported cannabis use. However, as prevalence estimates generated by the Crime Survey of England and Wales do appear to be an underestimate of actual levels of cannabis use in the United Kingdom, further research is merited on this topic.