The findings from a survey of nearly 4,600 police-reported crashes between July 2005 and December 2007 indicate that missing just one to two hours of sleep at night nearly doubles one’s chance of a car crash the following day. Furthermore, driving after only four to five hours of sleep quadruples the risk. Researcher Dr. Brian Tefft comments, “This is the first study to actually quantify the relationship between lack of sleep and the risk of being involved in a motor vehicle crash.”
AAA Foundation for Traffic Safety, December 2016