In the spring of 2010, the Government of British Columbia announced new sanctions for drinking drivers. As part of an evaluation of the impact of these new sanctions, a random survey of drivers was conducted at pre-selected locations in British Columbia from Wednesday to Saturday nights in June 2010. The primary purpose was to gather information on the prevalence of alcohol use among night-time drivers to be used as a pre-legislation baseline for the evaluation. This study was also intended to extend the findings from a previous Roadside Survey to include a community in northern British Columbia as well as a community from the interior. An additional purpose of the survey was to gather information on the prevalence of drug use among drivers in the selected communities to complement and extend the information gathered as part of the 2008 Roadside Survey. Drivers were randomly sampled from the traffic stream between 21:00 and 03:00 and were asked to provide a voluntary breath sample to measure their alcohol use and an oral fluid sample to be tested subsequently for the presence of drugs. Of the 2,840 vehicles selected, 86% of drivers provided a breath sample and 71% provided a sample of oral fluid. Key findings include: • 9.9% of drivers had been drinking; • 7.2% of drivers tested positive for drug use; • Cannabis and cocaine were the drugs most frequently detected in drivers; • Alcohol use among drivers was most common on weekends and during late-night hours; drug use was more evenly distributed across all survey nights and times; • Alcohol use was most common among drivers aged 19 to 24 and 25 to 34; drug use was more evenly distributed across all age groups; and, • While driving after drinking has decreased considerably since 1995, the number of drivers with blood alcohol concentrations (BACs) sufficient to be subject to provincial sanctions (i.e., over 50 mg/dL ) or Criminal sanctions i (i.e., over 80 mg/dL) continues to be an area of concern. The results show that drug use among drivers is not uncommon and that the pattern of drug use by drivers differs from that of alcohol use. For example, whereas the prevalence of alcohol use increases during late night hours, particularly on Friday and Saturday nights, drug use appears more consistent across days and times. The different patterns of alcohol and drug use by drivers suggest that driving after drug use presents a unique behaviour that differs from driving after drinking, indicating the need for a separate and distinct approach to enforcement, public education, prevention, and research. In comparison to previous surveys conducted in British Columbia since 1995, there has been a considerable reduction in the proportion of drivers found to have been drinking. However, the proportion of drivers with BACs over 50 mg/dL and over 80 mg/dL remain high, suggesting the need for further initiatives directed specifically at these high-risk groups. (Author/publisher)
Abstract