The dangers of texting while driving gets more headlines and drunk driving remains one of the main causes of automobile accidents, but a large, new study published Monday helps explain why so many teens and young adults are involved in motor accidents.

Indiana State Police/AP

Motor Carrier Inspector Master Trooper Mike Probasco, left, looks over the remains of a box truck with its driver Dagoberto Perez, of Cicero, Ill. in November 2010. Perez, who said he fell asleep and veered off the road, was cited for being a fatigued driver. Both drivers received non-life threatening injuries.

They're sleepy.

Report after report shows it -- sleepy drivers cause car crashes. In the new study, researchers at The George Institute for Global Health in Sydney, Australia suggest that a long-term lack of sleep may not only cause immediate drowsiness at the wheel, but may affect a young driver’s judgment over time.

“Less sleep per night significantly increased the risk for crash for young drivers,” the researchers wrote in the American Medical Association journal JAMA Pediatrics.

Alexandra Martiniuk and colleagues studied the driving records of more than 19,000 young men and women, aged 17 to 24, who had just received their driver’s licenses. These new drivers had filled out questionnaires that included specific details about how many hours sleep they got each night in the previous month.

Then the researchers went through police records on road crashes for the next two years after the drivers were licensed.

 “Those who reported sleeping six or fewer hours per night had an increased risk for crash compared with those who reported sleeping more than six hours,” they wrote. The people who slept the least were 21 percent more likely to have been involved in a crash than those who got more sleep, Martiniuk’s team found.

On the weekends, the risk rose even more. Those who got six hours or less sleep on the weekend were 55 percent more likely to be in a crash than those who slept more.

It’s a global problem affecting not only young drivers, they noted. “For drivers of all ages, estimates in the United States, United Kingdom, and Australia report that between 5 percent and 30 percent of crashes are attributed to fatigue,” the researchers noted. “Not only are they more likely to have sleep-related crashes; these crashes are more likely to be fatal compared with other crash causes.”

 The AAA Foundation published a survey last year that found one in seven licensed drivers ages 16-24 admits they had fallen sleep at least once while driving in the past year and that 10 percent of all drivers say they’ve dozed off at the wheel. The Centers for Disease Control and Prevention found that 5 percent of adults aged 18 to 44 admitted to nodding off at the wheel.

One in six crashes with a fatality was caused by a drowsy driver, according to the National Highway Traffic Safety Administration (NHTSA).

The NHTSA says sleepy driving is involved in 100,000 crashes serious enough to generate a police report each year. Such crashes have killed more than 1,500 Americans and injured 71,000.

Sabrina Birch was one of those victims. According to the Daily Oklahoman and other media reports, Birch, 17, was thrown out of the pickup truck when her boyfriend, Colby Ruthardt, also 17, fell asleep at the wheel and crashed last November.  The Gracemont, Okla. teen died from her injuries.

Martiniuk’s team found some suggestion that a lack of sleep may affect other behaviors, too.

“Risky driving, sensation seeking, self harm ... and greater drug and alcohol intake were reported more often by individuals who obtained less sleep,” they reported. It’s not clear whether a lack of sleep was a cause or a symptom, but they said the finding  points the way to doctors, parents and others trying to help.

They also noted direct measures that can help prevent crashes caused by sleepy drivers. “Changes to road design (eg, tactile road edges and divided highways), as well as education campaigns, may help reduce crash risk,” they wrote.

“Using a rest stop, drinking coffee, and playing the radio while driving have been shown to be significantly protective against crashes, at least in the short term,” they added.

Related:

• Automakers look to curb drowsy driving
• One in 24 admits to nodding off at the wheel
• The dangers of drowsy teen drivers

Aping Vision / Getty Images stock

Researchers found 30 percent of pedestrians corssed the street while distracted. Many were texting.

They're a lot like Pavlov’s dogs, those people who hear the ping of a landing text message or email and immediately whip out their smartphone to respond.

Now researchers in Seattle have found 30 percent of those plugged-in pedestrians were crossing the street while peering at cellphone screens, listening to music, or otherwise not paying attention.

“I was surprised it was as prevalent as it is,” said Beth Ebel, who’s seen the consequences first-hand as director of the Harborview Injury Prevention and Research Center in Seattle and as a pediatrician at Seattle Children’s Hospital.

“I have seen a large increase in cases, anecdotally, both as a consequence of driving, walking and even while on horseback of people engaging in text messaging while in a task that requires concentration,” Ebel said. “The problem with text messaging is you are drawn into the communication, and so you are not thinking about what is around you. You do not have situational awareness.”

Ebel has also seen it herself while driving. “Sometimes I am stopped at a light and somebody walks in front of me, doesn’t catch my eye, doesn’t look at me,” she said.

Unfortunately, multi-tasking pedestrians are plentiful. Ebel’s team at the University of Washington watched 1,102 people crossing busy streets at 20 intersections at three different, randomly chosen times.

“Nearly one-third (29.8 percent) of all pedestrians performed a distracting activity while crossing,” they wrote in the journal Injury Prevention. “Distractions included listening to music (11.2 percent), text messaging (7.3 percent) and using a handheld phone (6.2 percent).”

In addition, those using their smart phones crossed more slowly, and were less likely to look around before stepping out into the street, Ebel’s team noted. They also crossed against the light more than undistracted pedestrians.

Sobering statistics show just how unsafe this is: The Centers for Disease Control and Prevention says 60,000 pedestrians are injured and 4,000 killed every year in this country. And other studies have shown that people using cellphones while driving -- even hands-free -- are as impaired as if they'd had a drink or two.

We know we shouldn’t text and walk. But we do it anyway. Why the dangerous disconnect?

“Your brain is hard-wired for this,” says Ebel, who noticed the effect of an electronic summons years ago when, as a physician, she got her first beeper. “To me, this is the most classic Pavlovian model that I can think of."

As every first-year psychology student knows, Pavlov ran a series of experiments with dogs in which he rang a bell and then gave them food. Soon, the dogs began to salivate when the bell rang.

"Text messaging is just the same,” Ebel said. “The phone rings, and we get a nice treat.”

The treat is a fun or interesting text message – certainly more rewarding than looking at traffic.

“Why are we surprised that this is happening? It almost compulsive or instinctual,” Ebel said.

The problem is -- how do we stop it? Pointing out this bad behavior to strangers won't work, according to Ebel.

“I don’t imagine that it is effective to yell at them or scold them,” she said. “The irony of a lot of the cellphone discussion is we all feel indignant when we see someone doing something so risky in front of our noses, but the reality is many of us are doing this.”

Ebel predicts the related issues of cellphone use while driving and pedestrian cellphone use will go the way of drinking and driving laws. It will be illegal first, then socially unacceptable, she said.

As for how representative Seattle is of the entire country, Ebel is not sure. She hopes other people will study pedestrian behavior in their communities and is offering her study materials to schools.

“This is a great kind of project a school could do,” she said. “It makes kids more aware of how unaware people are are when they are distracted.”

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By MyHealthNewsDaily Staff

The risk of being in a fatal car crash has grown for underage females who've been drinking, according to a new study.

In 2007, underage female drinkers had the same risk as underage male drinkers, whereas a decade prior, the risk for females was half that of males, according to the study.

The reasons for the increased risk for females are not clear, but it could be that young women are taking greater chances on the road, the researchers said.

"Young women who drink and drive may be behaving more like young men who drink and drive," study researcher Robert B. Voas, of the Pacific Institute for Research and Evaluation in Calverton, Md., said in a statement.

Still, the total number of young men involved in fatal alcohol-related wrecks is greater, because men drink more, Voas said.

The study also showed that, overall, a person's risk of being killed or involved in a fatal crash rose with drivers' blood-alcohol levels, regardless of their age.

Compared with sober drivers the same age, 16- to 20-year-olds who had a blood-alcohol level between .02 percent and .049 percent had nearly triple the risk of being in a fatal crash, and nearly quadruple the risk of dying in a single-vehicle crash.

Another finding of concern was that the risk of being in a fatal car crash for sober male drivers between ages 16 and 20 doubled between 1996 and 2007.

While the exact reasons aren't clear, "we speculate that it may have a lot to do with distraction," said study researcher Eduardo Romano, also of the Pacific institute. "Sober kids are more at risk, and we think it may be related to texting and the other new technologies they are using so much."

The findings highlight the need for drunken-driving prevention education in school for both boys and girls, and for efforts to curb distracted driving.

The findings are based on information from a government reporting system on fatal traffic accidents nationwide. The researchers compared blood-alcohol information from nearly 6,900 fatal crashes in 2006 with information from about 6,800 U.S. drivers who were part of the 2007 U.S. National Roadside Survey.

The study is published in the May issue of the Journal of Studies on Alcohol and Drugs.

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