Single vehicle crashes comprise about 30% to 40% of fatal and serious injury crashes in many jurisdictions. The study sought to identify the factors that contribute to an increased risk of occurrence of single vehicle crashes, an important step in developing countermeasures to address the problem. A case-control study was undertaken that compared single vehicle crashes within 200 km of Melbourne, Australia with control data from a random sample of cars and light trucks travelling through the same area. BAC data were essentially complete for drivers in fatal crashes and control drivers but were missing for almost half of the drivers in serious injury crashes. The effect of this missing data is likely to be one of increasing the proportion of positive BAC values in the known data for serious injury crashes and of inflating the calculated odds ratios for the involvement of alcohol in serious injury crashes. Possibly as a result of this factor, the proportion of drivers with BAC>0.05, among the drivers with BAC known, was almost statistically significantly higher in serious injury than fatal crashes. However, among the drivers with BAC levels greater than zero, drivers in fatal crashes were more likely to have BACs of 0.150 and above than drivers in serious injury crashes. The odds ratio associated with BAC values of 0.001 to 0.050 was higher and statistically significant for serious injury crashes compared with fatal crashes. The extent of missing blood alcohol concentration data for serious injury crashes complicated the interpretation of the prevalence and risks associated with alcohol in fatal and serious injury crashes. There is a clear need for improvements to the collection and recording of blood alcohol data in non-fatal (Author/publisher) For the covering abstract of the conference see ITRD Abstract No. E201067.
Samenvatting