The world's largest automaker released a study Wednesday that examined data from 8.1 million phone calls between October 1996 and May 2000. The results from GM--one of the largest providers of on-board, hands-free cell phone services--starkly contradict a wealth of academic research on driver distraction, including a report issued last week saying all cell phone use poses a driving hazard.
GM researchers found that, out of 8.1 million calls in nearly four years, users of GM's hands-free cell phone services crashed only two times. Furthermore, researchers found "no evidence" that the phone played a role in the crashes. GM executives say their study is the most comprehensive analysis of actual--not simulated or estimated--data in the world.
"We've seen a lot of research that has come out lately, saying there is no difference between hands-free and other cell phones," said Chet Huber, president of GM's satellite communications subsidiary OnStar. "This finding would say there's probably a significant difference...and the embedded cell phone is significantly safer."
GM's research comes as the automobile and electronics industries face off against safety advocates, who say any device--from a phone to a tiny handheld computer--distracts drivers and puts all motorists at risk.
A growing body of academic research seems to support safety advocates' bans, though automakers and electronics companies dispute those findings, which are largely based on test-track simulations and estimates.
For example, a study released Thursday by the University of Utah determined that any type of cell phone--even a hands-free model--slows a driver's response time and is more disruptive than other in-car diversions.
The Utah academics conducted their study by having 64 people respond to simulated traffic signals while either talking on a cell phone, listening to the radio or listening to an audio book. The cell phone users missed twice as many signals as the people listening to the radio or audio books, researchers determined, regardless of whether they were using a handheld phone or a hands-free unit.
In a separate study conducted by Carnegie Mellon University and published in the Aug. 1 issue of NeuroImage, researchers used magnetic resonance images to compare what happens in people's brains when they do more than one complex task simultaneously. Researchers suggested that the brain can muster a finite amount of attention, and people performing two demanding tasks at the same time do neither as well as they do each one alone.
The study, led by psychology professor Marcel Just, did not specifically examine the brain activity of people driving cars and talking on hands-free phones. But Just said the study could be applied to the driver-distraction debate.
For instance, he extrapolated, the brain is likely unable to fully concentrate on the road while having any conversation--even one on a hands-free phone. The brain's ability to concentrate on the road might become especially hampered, he said, when a third element is thrown into the mix, such as a nearby lightning storm or an obstacle on the road.
A link between cell phones and accidents was reported as early as 1997 in The New England Journal of Medicine. Back then, Dr. Donald Redelmeier of the University of Toronto and Dr. Robert Tibshirani of Stanford University determined that talking on a cell phone while driving--even a hands-free phone--quadrupled the risk of being in an accident.
The pair surmised that keeping the driver's mind focused on the road is more important than keeping his or her hands on the wheel. They recently revisited their 1997 study for the Canadian Medical Association Journal, finding that they may have originally underestimated the risk. They suggested that cell phone bans for drivers might be justified.
The GM study comes at a critical time in the driver-distraction debate. New York state banned the use of handheld phones in cars in June, and Gov. George Pataki is expected to make the law effective Nov. 1. Several foreign countries, including Australia, fine drivers who use handheld phones behind the wheel.
The U.S. Congress is also considering a bill that would curtail cell phone use while driving, requiring people to dial, talk and listen via voice-activated, hands-free devices and headsets. Forty states have considered similar limits, according to the National Conference of State Legislatures, and a small number of them are mulling whether to ban the use of all cell phones--both hands-free and handheld devices--while drivers are on the road.
Although GM executives did not dismiss the growing body of academic research based on simulations at test tracks, they insisted Wednesday that their research was accurate. GM says its survey is the world's first analysis of a large database of actual, not estimated or simulated, information regarding crashes at the same time a cell phone was in use.
In addition to the one in 4 million figure, GM researchers found that only one in 6 million drivers were in an airbag-deploying crash within 10 minutes of calling an OnStar adviser. Again, statisticians found "no evidence" that the phone call itself played a role in the crash.
To be sure, GM has a vested interest in promoting the safety of hands-free devices; the automaker has 1.4 million subscribers to its OnStar satellite communications system, which is by far the auto industry's largest effort to wire the automobile. The automaker has aggressive goals for OnStar's profitability, and the subsidiary is quickly expanding to other forms of in-vehicle entertainment and updates.
GM researchers examined only crashes that were so bad that they caused the vehicles' airbags to deploy. They did not attempt to measure whether distracted drivers swerved and caused other drivers to crash. They also did not measure the potential impact of less-severe mishaps such as fender benders, sideswipes or other non-airbag-deploying accidents caused by veering out of a lane or onto a shoulder.
The data was restricted to calls placed to the OnStar Virtual Adviser system. OnStar advisers provide subscribers with traffic information, driving directions and safety advice after subscribers push a button in their cars. The hands-free system does not require subscribers to dial phone numbers, wear a headset or look at screens or dial pads.
GM is rolling out another OnStar program, Personal Caller, which will allow subscribers to make calls to anyone--not just OnStar advisers who provide directions and other straightforward information. But executives said Personal Caller does not necessarily present more danger by opening the door to more stressful phone calls with stern bosses or angry spouses.
Bill Kemp, executive director of safety communications at GM, said calls to Virtual Adviser require a similar amount of mental concentration as regular phone calls to friends, colleagues and family.
"We've had many, many phone calls where people are lost and advisers are on the phone with them for 10 or 15 minutes before people find an onramp to the expressway," Kemp said. "Those conversations are every bit as engaging as any conversation with anyone you might call."