Asleep at the Wheel:

The Prevalence and Impact of Drowsy Driving

Background

• Most past studies of crash data estimate roughly 1% - 4% of crashes involve a drowsy driver

BUT

• Many researchers believe that official statistics underestimate the prevalence of drowsy driving

AND

• A few studies using different data and methods have suggested that the prevalence of drowsy driving may be much higher

The Study

Available online at www.AAAFoundation.org

Published November 8, 2010

Part I: Prevalence of Drowsy Driving among Drivers

Method

•Data collected as part of the AAA Foundation’s 2010 Traffic Safety Culture Index

•Nationally-representative telephone survey of 2,000 U.S. residents 16 and older, conducted May 11 – June 7, 2010

•Asked respondents about experiences with falling asleep at the wheel and general drowsy driving

Key Findings•41% reported having “fallen asleep or nodded off” while driving at least once in their lifetime

•11% in past year• 4% in past month

•27% said they had driven while they were “so sleepy that [they] had a hard time keeping [their] eyes open” in the past month

Additional Findings• Men much more likely than women (52% vs. 30%) to report having fallen asleep while driving

•Only 21% reported they had been driving for three hours or more when they fell asleep at the wheel; 59% said they had been driving for less than an hour before falling asleep;

• Only 28% said they felt sleepy when they started driving; 71% said they felt awake enough to drive

Part II: Proportion of Crashes Involving a Drowsy Driver

Method•Analyzed data from nationally-representative sample of crashes in which a car, light truck, van, or SUV was towed

• Years 1999 – 2008

• Sample included 80,821 vehicles involved in 47,597 crashes

• Drowsiness = unknown in 45% of cases

used statistical technique of multiple imputation to estimate proportionthat were drowsy

% of Crashes that Involved a Drowsy Driver

7.0%

13.1%

16.5%

All Crashes

Admitted to Hospital

Fatal

Maximum injury severity in crash

Data: Representative sample of 47,597 crashes in which a passenger vehicle was towed, 1999 – 2008. (National Automotive Sampling System Crashworthiness Data System, compiled by National Highway Traffic Safety Administration) Missing values of drowsiness imputed 10 times and averaged.

Additional Findings• Drivers 16-24 years old nearly twice as likely to be involved in a drowsy driving crash as drivers ages 40+

•Two out of three drivers involved in a drowsy driving crash were men

• Drivers travelling alone nearly 2x as likely to be in drowsy driving crash compared to drivers with passengers

• 57% of drowsy driving crashes were single vehicle crashes where driver drifted out of lane or off road

Tips for Avoiding Drowsy Driving• Get at least 6 hours of sleep the night before a

long trip (preferably 8; no less than 6)

• Travel at times you are normally awake; stay overnight en route instead of trying to drive straight through

• Schedule a break every 2 hours or 100 miles

• Don’t work all day and drive all night

• Travel with a passenger who is awake

• Drink a caffeinated beverage, but remember that it takes 30 minutes for effects to kick in

For more information, go to:

AAAFoundation.org

The AAA Foundation for Traffic Safety is a 501(c)(3) public charity located in Washington, DC that is dedicated to saving lives and reducing injuries.

It is supported by donations from AAA/CAA Clubs, AAA/CAA members, and other organizations associated with AAA/CAA.