In a survey of 1,813 Ontario adults, about 90% agreed that cannabis-impaired driving increases crash risk, but only 55% of those who had driven high in the past year agreed, with males and frequent users most likely to dismiss the risk.
Public health communicators, traffic safety advocates, and policy makers designing cannabis-impaired driving prevention strategies.
Only 55% of past-year cannabis-impaired drivers acknowledged crash risk
What the researchers found
About 90% of adults agreed DUIC increases collision risk, dropping to 55% among past-year DUIC drivers. Being male, less educated, and using cannabis monthly or more were associated with disagreeing that DUIC increases crash risk. Safety perceptions but not legal risk perceptions were associated with actual DUIC behavior among cannabis-using drivers.
Why it matters
Risk perception drives behavior. The finding that safety concerns, not fear of getting caught, predicted whether cannabis users drove high suggests prevention campaigns should focus on crash risk messaging rather than legal consequences.
The numbers in context
1,813 adults; ~90% overall agreed DUIC increases crash risk; 55% of past-year DUIC drivers agreed; males, less educated, monthly+ users most likely to dismiss risk
How the study worked
Cross-sectional telephone survey of 1,813 adults aged 18+ in Ontario, Canada (2017 CAMH Monitor). Multivariable logistic regression assessed factors associated with DUIC risk perceptions and the relationship between perceptions and DUIC behavior.
What this study cannot tell us
Cross-sectional design. Self-reported DUIC behavior subject to social desirability bias. Ontario-specific data may not generalize. Pre-legalization data collection (2017).
How to read the evidence
Solid population-based telephone survey with multivariable analysis, though cross-sectional and pre-legalization timing limit conclusions.
When this study was published
Published in 2021 using 2017 data.
The bigger picture
The gap between general population risk perception (90% concerned) and active DUIC driver perception (55% concerned) parallels patterns seen with alcohol-impaired driving and suggests targeted messaging for the highest-risk groups is needed.
Questions still open
- Have risk perceptions changed since recreational legalization in 2018? Would targeted safety messaging reduce DUIC among male frequent users? How does cannabis-impaired driving compare to alcohol-impaired driving in this population?
Common questions
Do people think driving high is safer than driving drunk?
Does fear of getting caught prevent cannabis-impaired driving?
Read the original research
Driving under the influence of cannabis risk perceptions and behaviour: A population-based study in Ontario, Canada.
Preventive medicine, 153, 106793
Citation
McDonald, André J; Hamilton, Hayley A; Wickens, Christine M; Watson, Tara Marie; Elton-Marshall, Tara; Wardell, Jeffrey D; Rueda, Sergio; Roerecke, Michael; Stoduto, Gina; Mann, Robert E. (2021). Driving under the influence of cannabis risk perceptions and behaviour: A population-based study in Ontario, Canada.. Preventive medicine, 153, 106793. https://doi.org/10.1016/j.ypmed.2021.106793