A third of young cannabis-using drivers in Ontario reported driving under the influence, with 42% planning to do so again

Among 426 young Ontario drivers, 33.3% reported past cannabis-impaired driving and 42% indicated at least a slight chance of doing so in the next year, with past behavior and low moral awareness as key predictors.

Colonna, Robert et al.·Journal of safety research·2021·Moderate EvidenceCross-Sectional
RTHC-03071Cross SectionalModerate Evidence2021RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=426

What This Study Found

33.3% of respondents reported past DUIC and 42% indicated future DUIC intention. Six predictors of DUIC intention emerged: past DUIC incidence, perceived conviction penalty rate, moral awareness, perceived dangerousness, minor accident risk perception, and vicarious punishment avoidance.

Key Numbers

426 respondents; 52.6% female; 83.6% had used cannabis; 69.5% past-year use; 33.3% reported DUIC; 42% intended future DUIC; 6 significant predictors identified

How They Did This

Cross-sectional validated questionnaire based on general deterrence and prevention theory, administered to 426 young drivers (ages 16-24) in Ontario, Canada. Ordinal regression examined predictors of DUIC intention.

Why This Research Matters

The high prevalence of both past and intended DUIC among young drivers, combined with identifiable attitudinal predictors, provides clear targets for prevention programs.

The Bigger Picture

The finding that moral awareness and perceived dangerousness predict DUIC intention suggests that prevention programs emphasizing personal responsibility and real crash risk may be more effective than fear-based approaches focused solely on legal consequences.

What This Study Doesn't Tell Us

Self-selected sample of young drivers, Ontario-specific, cross-sectional design, self-reported DUIC which may be underreported, questionnaire validation was part of the same study.

Questions This Raises

  • ?Would interventions targeting these six predictors actually reduce DUIC behavior?
  • ?Has legalization changed any of these attitudinal predictors?
  • ?Are there effective brief interventions for DUIC prevention?

Trust & Context

Key Stat:
33.3% reported past DUIC and 42% intended to drive cannabis-impaired again
Evidence Grade:
Validated questionnaire study with robust regression analysis in a targeted population
Study Age:
Published in 2021 from Ontario, Canada, after cannabis legalization.
Original Title:
Young drivers' determinants of driving under the influence of cannabis: Findings from the Youth Cannabis and Driving Survey (YouCanDS).
Published In:
Journal of safety research, 78, 229-241 (2021)
Database ID:
RTHC-03071

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

How common is cannabis-impaired driving among young people?

In this Ontario study of 426 young drivers, a third had driven under the influence of cannabis, and 42% indicated they would likely do so again in the next year.

What makes young people drive after using cannabis?

The strongest predictors were having done it before, low moral concern about the behavior, low perception of danger, and not believing they would be caught and penalized.

Read More on RethinkTHC

Cite This Study

RTHC-03071·https://rethinkthc.com/research/RTHC-03071

APA

Colonna, Robert; Hand, Carri L; Holmes, Jeffrey D; Alvarez, Liliana. (2021). Young drivers' determinants of driving under the influence of cannabis: Findings from the Youth Cannabis and Driving Survey (YouCanDS).. Journal of safety research, 78, 229-241. https://doi.org/10.1016/j.jsr.2021.05.001

MLA

Colonna, Robert, et al. "Young drivers' determinants of driving under the influence of cannabis: Findings from the Youth Cannabis and Driving Survey (YouCanDS).." Journal of safety research, 2021. https://doi.org/10.1016/j.jsr.2021.05.001

RethinkTHC

RethinkTHC Research Database. "Young drivers' determinants of driving under the influence o..." RTHC-03071. Retrieved from https://rethinkthc.com/research/colonna-2021-young-drivers-determinants-of

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.