Single-vehicle accidents in Sweden: A comparative study of risk and risk factors by age

Abstract

Single-vehicle accidents account for almost 50% of all injured passenger car occupants in Sweden. Young male drivers account for a high percentage of these accidents. This study investigates how the single-vehicle accident risk per distance driven varies by age and sex, and attempts to explain the variability by examining factors related to the driver, the vehicle, and the road. To this end, single-vehicle accidents resulting in personal injury as reported by the police for 1984 were used; data on traffic exposure were taken from a travel survey carried out by Statistics Sweden in 1984; and 467 (62%) of the severely injured drivers answered a questionnaire regarding possible risk factors. The data used indicated that men 18–19 years of age were exposed to an eight times greater risk level compared to men 25–54 years of age; there was a 40 times greater risk level on Friday and Saturday evenings and nights, compared to the average risk level observed for all drivers at all times; one third of the drivers were suspected by the police to have been driving when drunk; and suspected drunk driving was much more common among middle-aged drivers as among young drivers. However, the results from the questionnaire show no, or very little, difference between age groups in reported frequencies of different risk factors, In fact, neither drunk driving, speeding, fatigue, illness, vehicle, road conditions, or lack of drivers license could explain the much higher risk level among young as compared to middle-aged drivers.