Aug. 13, 2010 (San Diego) -- Ditch the phone if you drive. That's the bottom line of a new study that found using hands-free headsets while driving doesn't result in fewer accidents, echoing the results of many previous studies.
''When you are on the phone, you are only using part of your brain to drive," says researcher David Schwebel, PhD, vice-chair and professor of psychology at the University of Alabama, Birmingham, who presented the findings today at the annual meeting of the American Psychological Association in San Diego.
''My advice is not to talk on the phone while you are driving, ever," he says.
Eight states prohibit all drivers from using handheld cell phones while driving. Some states prohibit all cell phone use by novice drivers.
New Data on Hands-Free Headsets
Schwebel and colleagues evaluated the practices of 110 college students, with an average age of 20, who were asked to report their use of hands-free and handheld phones in general and while driving. They also reported the number of motor vehicle accidents and traffic citations over the past five years.
''There was not a statistical difference in those using handheld or hands-free,'' Schwebel tells WebMD.
''Statistically they were in an equal number of crashes," he says.
''What we found is that the amount of time they used hands-free had no relation to crash history or accident history."
Those using hands-free headsets while driving did have fewer traffic tickets, Schwebel's team found. But he speculates the most likely explanation for that is another factor -- that older people and women may be more conscientious drivers, using hands-free headsets because they are viewed by some as safer.
"It seems people who are conscientious are going to use hands-free and will follow traffic rules more closely," he says.
Cell Phones and Driving: Safety Issues
While some say hands-free cell phone use while driving allows motorists to keep their hands free to cope with an emergency, Schwebel says the main issue is distraction while talking on the phone, whether your hands are free or not.
"What people [researchers] have discovered is, it's really the cognitive distraction of talking on the phone that causes the risk," he says. ''Your mind is elsewhere when you are on the phone, trying to do two things."
To those who say a passenger is equally distracting, Schwebel disagrees. "Passengers tend to stop talking or recognize a pause in the conversation when drivers are in a difficult situation," he says, but those on the other end of the cell phone may not.
''Driving may seem routine, but it isn't," Schwebel says. "Driving is hard and it requires your full brain capacity to drive safely. When you are on the phone, you are only using part of your brain to drive."
''The findings appear to replicate the work done in our lab and other labs over the last 10 years, showing that the negative impact on driving behavior does not differ between hands-free and handheld [cell phones]," says Frank Drews, PhD, associate professor of psychology at the University of Utah, Salt Lake City.
By now, he tells WebMD, the data have been well-duplicated.
Hands-Free Headsets: Industry View
In response to the new study, the Bluetooth SIG (Special Interest Group), a trade organization, issued a statement. It reads: "Using a Bluetooth enabled hands-free device allows users to keep both hands on the wheel while keeping their eyes on the road and ensures drivers are complying with distracted driving laws. Bluetooth wireless headsets and speakerphones provide an alternative to those people looking to communicate from the car, allowing them to do it with their hands-free. All drivers should assess their unique driving situation and make calling decisions accordingly."