Fatigue in multiple-car fatal accidents.

In a re-examination of 334 fatal multiple car accidents, without any reasonable explanation besides possible intoxication, 205 drivers were found responsible for the accident. Twenty-one of these accidents happened between midnight and 0600 h and 11 of the drivers were found to be intoxicated with a blood/alcohol content (BAC) of more than 0.080%. The remaining 184 accidents took place during the rest of the day and 55 drivers were intoxicated. By comparing this apparent over-representation of intoxicated drivers in night-time accidents with that of a control group of no less than 15,923 drivers, it was possible to convert this over-representation into an under-representation. This decline in accidents while under influence seems to indicate another human accident factor specific to night-time traffic. It is concluded that fatigue is an overlooked but most obvious cause of otherwise unexplainable accidents in the night-time traffic.