In their study, researchers made the 40 volunteers use a driving simulator four times- once with no distractions, once using a handheld cell phone, once using a hands-free cell phone and once while intoxicated to a 0.08 percent blood-alcohol level after drinking vodka and orange juice. (the average legal level of impairment in the U.S.)
Researchers found that three of the volunteers' bumped into the simulated car in front of them, while noting that none of the three was drunk but they were talking on cell phones.
They found that the cell phone talking drivers drove slightly more slowly, were 9 percent slower to hit the brakes, and varied their speed more as compared to drivers that had no distractions.
On the other hand the drunk drivers drove a bit more slowly than both drivers that had no distractions and telephone users, yet more aggressively.
Frank Drews, an assistant professor of psychology at the University of Utah who worked on the study said, "Driving while talking on a cell phone is as bad as or maybe worse than driving drunk," noting that 40 percent of the 42,000 annual U.S. traffic fatalities were due to alcohol.
The researchers pointed out that alike the drunk people, the cell phone users did not believe themselves to be affected.
"If legislators really want to address driver distraction, then they should consider outlawing cell phone use while driving," Frank said.
The research has been published in the summer 2006 issue of Human Factors: The Journal of the Human Factors and Ergonomics Society.
