A New Study Shows Tired Driving as Dangerous as Drunk Driving

December 8, 2016
A New Study Shows Tired Driving as Dangerous as Drunk Driving

Getting behind the wheel of a car after only four or five hours of sleep increases the risk of being involved in an auto accident as much as driving drunk per to new research by AAA.

The December 2016 AAA Foundation for Traffic Safety report contained a study, Acute Sleep Deprivation and Risk of Motor Vehicle Crash Involvement, in which researchers examined data from the U.S. Department of Transportation's sample of vehicle collisions between July 3, 2005, and December 31, 2007. To qualify for the study, each crash had to involve at least one light vehicle that was towed due to damage or medical services dispatched to the scene. A total of 7.234 drivers in 4,571 crashes were included.

The number of hours each driver slept within 24 hours was used by researchers to calculate their risk of collision. They also focused on whether the drivers committed an unsafe or illegal action or error from the determination of the on-scene investigators.

According to their findings, as many as 21% of fatal auto accidents involve drowsy driving. Approximately 13% of crashes requiring a trip to the emergency room, and 7% of all crashes, are caused by sleep-deprived drivers.

Drivers who had less than four hours sleep in the last 24 hours had a crash rate that was 11.5 times greater than those who had slept for seven hours or more. Drivers who received four to five hours of sleep within the past 24 hours had an accident rate of 4.3 times greater than those that had enough sleep. This rate is similar or worse than the crash rate for drivers with a blood alcohol content of 0.08 or higher.

The accident rate for drivers who slept six to seven hours in the past 24 hours was only 1.3 times greater than those who got the full seven hours of sleep.

Drivers who typically sleep only four to five hours per night were still at 5.4 times greater risk of a crash than the seven-hour sleepers.

In scenarios where a driver normally got the seven hours of sleep each night but reported sleeping one to two hours less the night before had an increased accident risk of 1.3 times greater. Drivers who slept two to three hours less were three times more likely to be involved in a crash than other drivers. For a driver with less than four hours sleep their chance of an accident increased to 10 times that of those who received their typical amount of sleep.

A study conducted previously by AAA in November 2015 found that more than two of five drivers admitted to falling asleep or nodding off while driving at least once in their lifetime. Nearly 20% of all drivers reported falling asleep at the wheel three or more times in their lifetime.

Researchers caution that the recent study data may underestimate the risks since the data was not inclusive of accidents that occur between midnight and 6AM. Other studies have shown the effects of sleep deprivation to be greatest in the early morning hours.

According to the U.S. Centers for Disease Control and Prevention, about 12 % of adults indicate they sleep less than five hours a day.

In their report the study authors wrote, “A consensus working group convened by the National Sleep Foundation concluded that based on the totality of evidence available at the time of their meeting, drivers who have slept for less than two hours in the past 34 hours are not fit to operate a motor vehicle.”

If a person drives a motor vehicle while sleep deprived and causes an accident, that person can be held legally responsible. Dolman Law Group Accident Injury Lawyers, PA represents victims who have been injured in motor vehicle accidents. If you or someone you care about was injured in a motor vehicle crash, contact Dolman Law Group Accident Injury Lawyers, PA today for a free evaluation of your case. Call 727-451-6900.

Dolman Law Group Accident Injury Lawyers, PA
800 North Belcher Road
Clearwater, FL 33765

(727) 451-6900


Matthew Dolman

Clearwater Personal Injury and Insurance Attorney

This article was written and reviewed by Matthew Dolman. Matt has been a practicing civil trial, personal injury, products liability, and mass tort lawyer since 2004. He has represented over 11,000 injury victims and has served as lead counsel in over 1000 lawsuits. Matt is a lifetime member of the Million Dollar Advocates Forum and Multi-Million Dollar Advocates Forum for resolving individual cases in excess or $1 million and $2 million, respectively. He has also been selected by his colleagues as a Florida Superlawyer and as a member of Florida’s Legal Elite on multiple occasions. Further, Matt has been quoted in the media numerous times and is a sought-after speaker on a variety of legal issues and topics.

Learn More