Researchers identified 571 car drivers or passengers who were admitted to hospital or died as a result of a car crash in the Auckland region of New Zealand between April 1998 and July 1999. A further 588 people driving on the region’s roads during the study period were used as a control group.
They found an eightfold increased risk if drivers reported sleepiness, an almost threefold risk for drivers who reported five hours or less of sleep in the previous 24 hours, and a five fold risk for driving between 2am and 5am.
Reducing these three behaviours may reduce injuries or death by up to 19%, say the authors. It also provides some simple messages with regard to specific driver behaviours in place of general advice against driving while sleepy, they conclude.