Citation

Wettlaufer A, Florica RO, Asbridge M, Beirness DJ, Brubacher J, Callaghan R, Fischer B, Gmel G, Imtiaz S, Mann RE, McKiernan A, Rehm J. Drug Alcohol Depend. 2017; 173: 185-190.

Affiliation

Centre for Addiction and Mental Health, Canada.

Copyright

(Copyright © 2017, Elsevier Publishing)

DOI

10.1016/j.drugalcdep.2016.12.024

PMID

28273616

Abstract

INTRODUCTION: In 2012, 10% of Canadians used cannabis and just under half of those who use cannabis were estimated to have driven under the influence of cannabis. Substantial evidence has accumulated to indicate that driving after cannabis use increases collision risk significantly; however, little is known about the extent and costs associated with cannabis-related traffic collisions. This study quantifies the costs of cannabis-related traffic collisions in the Canadian provinces.

METHODS: Province and age specific cannabis-attributable fractions (CAFs) were calculated for traffic collisions of varying severity. The CAFs were applied to traffic collision data in order to estimate the total number of persons involved in cannabis-attributable fatal, injury and property damage only collisions. Social cost values, based on willingness-to-pay and direct costs, were applied to estimate the costs associated with cannabis-related traffic collisions. The 95% confidence intervals were calculated using Monte Carlo methodology.

RESULTS: Cannabis-attributable traffic collisions were estimated to have caused 75 deaths (95% CI: 0-213), 4407 injuries (95% CI: 20-11,549) and 7794 people (95% CI: 3107-13,086) were involved in property damage only collisions in Canada in 2012, totalling $1,094,972,062 (95% CI: 37,069,392-2,934,108,175) with costs being highest among younger people.

DISCUSSION: The cannabis-attributable driving harms and costs are substantial. The harm and cost of cannabis-related collisions is an important factor to consider as Canada looks to legalize and regulate the sale of cannabis. This analysis provides evidence to help inform Canadian policy to reduce the human and economic costs of drug-impaired driving.

Keywords: Cannabis impaired driving


Copyright © 2017 Canadian Centre on Substance Abuse. Published by Elsevier B.V. All rights reserved.

Language: en

Keywords

Canada; Cannabis; Costs; Harm; Traffic collision