Blood samples collected from 2500 non-fatally injured drivers involved in road crashes were analysed for the presence of alcohol, cannabinoids, benzodiazepines and stimulants. Evaluation of the causal role of the drug in the crash was based on culpability analysis using data collected at the crash scene. A clear causal role was found for alcohol, with increased culpability rates at high blood alcohol concentrations (BACs). Benzodiazepine use was also associated with higher culpability when those with very low concentrations were excluded. Consistent with earlier research, THC was not associated with increased culpability. Relatively few drivers tested positive for stimulants and there was no clear evidence of greater culpability. Overall, alcohol plays the greatest role in road crashes, but benzodiazepines also have a significant effect.
Samenvatting