In Spain, there are several sources of information for traffic injury data. The source of information that provides detailed data on the circumstances of the crashes is based on the information collected by officers responsible for traffic surveillance and control, who complete the appropriate statistical questionnaires. Traffic police officers monitor the condition of those injured during the first 24 hours after the crash occurred, specifying whether the person injured died within that period, spent more than 24 hours in hospital, was considered serious or slightly injured, or was not taken to hospital in that period of time. This is done by obtaining the required information from hospitals.