The World Health Organization defines a road traffic accident as a collision occurring on a public road and involving at least one vehicle, which may have health consequences for the people involved.
Road traffic accidents are a high-priority public health issue, being responsible for a large number of deaths and temporary and permanent disabilities worldwide. This carries huge social, human and economic costs, and explains the attention given to road safety by the health protection departments and health systems of all countries. The large majority of serious and fatal accidents are caused by improper behaviour, including: speeding, distracted and reckless driving, failure to give way or maintain a safe distance, driving under the influence of alcohol and other psychoactive substances.