In the spring of 2010, the Government of British Columbia announced new measures to deal with drinking drivers that would be implemented in September 2010. The Immediate Roadside Prohibition (IRP) program involved a series of increased sanctions applied at roadside for drivers with blood alcohol concentrations (BACs) starting at 50 mg/dL. As part of an evaluation of the impact of the IRP legislation on the drinking-driving behaviour of drivers, a survey of drivers was conducted in five communities in British Columbia in June 2010 and again in June 2012. Drivers were randomly selected from the traffic stream between 21:00 and 03:00 on Wednesday through Saturday nights and 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 2,513 vehicles selected for the survey in 2012, 89% of drivers provided a breath sample and 70% provided a sample of oral fluid. Driving after drinking decreased significantly following the introduction of IRP. In particular, the percentage of drivers with BACs over 80 mg/dL decreased by 59%; drivers with BACs of at least 50 mg/dL decreased by 44%. Compared to similar roadside surveys dating back to 1995, the levels of drinking and driving were the lowest ever recorded. The decreases in drinking and driving were not restricted to specific sub-groups of drivers but were universal across age groups, sex, and communities. The results also revealed a changing pattern of drinking of driving. For example, the typical pattern of increased drinking and driving on weekend nights was not observed and the prevalence of drinking drivers on the road during late night hours was less than half that found in 2010. No driver with a BAC over 80 mg/dL reported that they were coming from a bar, pub or nightclub. Together, these findings are evidence of a profound and universal change in drinking and driving in British Columbia following the introduction of the IRP legislation in September 2010. The prevalence of drug use by drivers in 2012 did not change from the levels reported in 2010. Overall, 7.4% of drivers tested positive for drugs; in 2010 7.2% of drivers were drug-positive. Once again, cannabis and cocaine were the most commonly detected substances. As was the case in previous surveys, the pattern of drug use by drivers was more consistent than alcohol use across age groups, days of the week, and time of night. It was evident from the interviews and questionnaires that drivers in British Columbia were aware of the new IRP legislation and remain concerned about impaired driving. They appear willing to accept tough measures in support of efforts to improve the safety of the roads. Several challenges remain to sustain the observed changes and further reduce the impact of impaired driving. Male drivers between 25 and 34 years of age remain the most likely to drive after consuming impairing amounts of alcohol. Although females are less likely than males to drink and drive, when they do, they tend to do so with elevated BACs. Of the drinking drivers that remain, they tend to be frequent and/or heavy drinkers. Also, the overall prevalence of drug use among drivers has not changed but there were increases in drug use among certain subgroups. These issues continue to be in need of further study and extra attention is required to develop appropriate and effective policies and programs for education, prevention, enforcement, and rehabilitation. (Author/publisher)
Samenvatting