Drowsy driving plays a role in nearly eight times as many accidents as federal estimates suggest, according to a study released Thursday.
Using in-vehicle camera footage of thousands of drivers who had agreed to participate in the study, the AAA Foundation for Traffic Safety concluded that motorists are falling asleep at the wheel at alarming rates.
The AAA study examined more than 700 crashes, analyzing three minutes of video of drivers' faces leading up to the accidents. They used a scientific gauge to determine whether the driver was sleepy.
In about 9.5% of crashes, drowsiness was a factor. And it was a key factor in 10.8% of accidents that caused serious property damage.
The finding differs with the result of investigations by federal researchers, who believe sleepiness is a cause in a far smaller percentage of crashes in the U.S.
The National Highway Traffic Safety Administration (NHTSA) had reported in 2017 that driver drowsiness was involved in 1.4% of all police-reported crashes, 2% of crashes resulting in injuries and 2.4% that resulted in death from 2011 to 2015.
The primary reason for the disparity between government statistics and the AAA is study is likely that it's extremely difficult for law enforcement officials to determine when drowsiness was a factor unless the driver admits it.
Kerrie Warne, a St. Louis-area resident whose 18-year-old son was killed when he fell asleep while traveling on the highway, said it's critical to build awareness of the severity of driving while tired.
"My son could have been the poster child for a drowsy-driving crash," said Warne, who later founded a non-profit called Tyler Raising Education for Drowsy Driving to educate people on the dangers. "We have to do something because parents shouldn’t have to bury their kids, and brothers and sisters shouldn’t have to bury their siblings."
Given the percentages, drowsy driving may have accounted for several thousand of the more than 37,000 American roadway deaths in 2016, said William Horrey, group leader of the AAA Foundation for Traffic Safety's Traffic Research Group. That's the latest year for which figures are available.
The AAA Foundation recommends sleeping at least seven hours a night before driving.
But about 35% of U.S. drivers sleep less than that, according to the Centers for Disease Control and Prevention. Getting just four or five hours can more than quadruple the risk of an accident, according to AAA.
"Really the only effective countermeasure for drowsiness is sleep, so we want to encourage people to really try to prioritize and allocate enough time to get a good night’s rest," Horrey said.
Part of the problem is that many Americans need to change their lifestyles to sleep more, said Jennifer Pearce, a Virginia resident whose sister Nicole Lee was killed in a drowsy-driving crash in 2008.
"It’s such a cultural issue," said Pearce, who said she tries to get eight hours of sleep every night. "It’s almost like it’s cooler, even as adults, to be able to do these monumental things on as little sleep" as possible.
You know you shouldn't be behind the wheel if you're having trouble keeping your eyes open, drifting from your lane or having difficulty recalling the last several miles.
Slapping yourself to stay awake? That won't work. Neither will drinking caffeine or rolling down the windows.
Those are temporary measures that fade fast, experts said.
In addition to getting enough sleep, it's best to avoid driving at times you'd normally be sleeping. And drivers should certainly avoid medications that cause drowsiness. They should also schedule breaks.
A short nap at a rest stop can make a big difference.
"We really don’t want to be relying on our bodies to tell us that we’re fatigued," Horrey said. "We really want to be aware and avoid it in the first place."
Warne said another good step is to turn off digital devices at least an hour before bed to ensure a good night's rest.
She said the federal government needs to take drowsy driving more seriously by investing heavily in public education.
An NHTSA spokesperson was not available for comment for this story.
The AAA report was based on footage from the federally funded Second Strategic Highway Research Program’s Naturalistic Driving Study, which involved monitoring 3,593 drivers from six locations for several months.
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