Young drivers' determinants of driving under the influence of cannabis

Driving under the influence of cannabis (DUIC) is proven to increase the risk of collisions and is most common among young drivers (ages 16 to 24). However, little is known about the specific determinants of DUIC behavior among youth, which limits the capacity to develop evidence-based prevention and intervention efforts. This study developed and evaluated a youth DUIC questionnaire, which was used to establish the DUIC determinants of young drivers. The questionnaire was based on the theoretical framework of general deterrence and general prevention. Data obtained included: demographics, past cannabis use and DUIC experiences, DUIC intention, experiences riding as a passenger with someone DUIC, knowledge and credibility of the law, attitudes towards DUIC, and social controls. The resulting questionnaire was validated for a sample of 426 young drivers in the province of Ontario, Canada. An ordinal regression was conducted to examine the relationships between questionnaire items and DUIC intention. The questionnaire displayed good construct validity and internal consistency across four out of five domains (KMO and Cronbach α values ≥ 0.70). Of the 426 respondents (52.6% female), 356 (83.6%) reported previous cannabis use, with 296 (69.5%) doing so in the past year, and 142 (33.3%) reporting DUIC. Furthermore, 179 (42%) study participants indicated at least a slight chance of DUIC in the next year. The regression analysis identified six variables predictive of DUIC intention: past DUIC incidence, perceived percent of those convicted that receive the penalty, moral awareness, perceived dangerousness, minor accident risk, and vicarious punishment avoidance. The study concludes that  preventive efforts should emphasize these determinants when designing targeted strategies and interventions.  These efforts should focus on educating the dangers and risk of a vehicle collision, that law enforcement has the capacity to apprehend and appropriately punish individuals DUIC, and that DUIC is wrong and socially unacceptable.