The objective of this study was to assess the incidence, time of day, and driver morbidity associated with vehicle accidents where the most likely cause was the driver falling asleep at the wheel. Two surveys were undertaken, in south-west England and the midlands, by using police databases or on the spot interviews. The subjects were drivers who were involved in 679 sleep related vehicle accidents. It is concluded that sleep related vehicle accidents are largely dependent on the time of day and account for a considerable proportion of vehicle accidents, especially those on motorways and other monotonous roads. As there are no norms for the United Kingdom on road use by age and sex for time of day with which to compare these data, the authors cannot determine what the hourly exposure versus risk factors are for these subgroups. The findings are in close agreement with those from other countries. (A)
Abstract