CHAPEL HILL – Overall, only 3.1 percent of North Carolinians are talking on cell phones at any given time while driving, a surprising new University of North Carolina at Chapel Hill study shows.
The prevalence rate was higher in the Piedmont -- 4.1 percent -- than in the mountains, which showed 2.2 percent of drivers using the devices, and in the coastal plain, which had 1.5 percent, researchers found.
“People we’ve discussed these numbers with have been surprised,” said Dr. Donald W. Reinfurt, deputy director of UNC’s Highway Safety Research Center. “Almost everybody thinks the rate is much higher, and a while back a local television reporter guessed 50 percent.
“ It’s fair to assume, however, that as more people get phones, the higher the percentage will be of people using them while driving. What is absolutely clear is that more and more crashes will involve cell phones.”
Reinfurt and colleagues conducted the study with support from the N.C. Governor’s Highway Safety Program and the cooperation of Col. Richard Holden, commander of the N.C. State Highway Patrol.
Traffic monitors observed drivers during daylight and noted if they were talking on cell phones at 85 sites across the state. In total, they observed for an hour-and-a-half at each site and saw more than 25,300 drivers, 14,059 of whom were stopped at intersections and 11,286 of whom were moving. Among moving drivers, 352 -- or 3.1 percent -- were chatting on the phone.
“Drivers who were using a cell phone while stopped at intersections were more likely to be driving without a front seat passenger, driving a sport utility vehicle, younger, white and using seat belts,” Reinfurt said. “Analysis of accident reports from three N.C. Highway Patrol areas suggest that about one in 600 crashes appeared to involve use of a cell phone while driving, but we believe that may be a serious underestimate.”
A computer search of all N.C. crash report narratives between Jan. 1, 1996, and Aug. 31, 2000, showed exponential growth in the frequency with which cell phone use was mentioned -- from 22 in 1996 to 231 for the first eight months of 2000, he said.
Cell phone use in cars increased somewhat during the average day from 2.7 percent in the morning to 3.5 percent in late afternoon, researchers found.
The UNC investigation also involved reviewing epidemiological studies of driving and cell phone use, case analyses of phone-related crashes and driver performance studies.
“It’s also absolutely clear from the research literature that talking on a cell phone while driving does elevate the risk of a crash,” Reinfurt said. “Using cell phones slows reaction times and degrades drivers’ tracking abilities.”
The overall 3.1 percent N.C. figure is consistent with a recent National Highway Transportation Safety Administration study showing 3 percent of drivers nationally talking on cell phones at any given time, Reinfurt said. That translates into 500,000 U.S. drivers.
“Because people usually won’t admit to officers that they were talking on phones at the time of their accidents, studies analyzing risk are notoriously difficult to do well, and it is far from clear just how much cell phones increase the risk of crashes,” he said. “We are a long way from solving this data problem.”
The risk now posed by cell phones will undoubtedly grow as cars and other vehicles increasingly come equipped with other distracting electronic devices such as information and satellite guidance systems and even fax machines, Reinfurt said.
Other elements of the UNC study included reporting on recent legislative activities regarding cell phone use while driving, pilot-testing a supplemental data form for highway patrol officers to record phone-related crashes and analyzing police report narratives indicating that cell phones were a factor in certain crashes.
In 2001, 144 phone-related bills have been considered in 44 state legislatures, the District of Columbia and Puerto Rico. In New York, for example, beginning Nov. 1, drivers were not allowed to use hand-held mobile phones except in emergencies. Two similar N.C. bills died in committee.
UNC’s Dr. Jane Stutts is in the middle of a major study for the AAA Foundation for Traffic Safety of all forms of distractions to drivers, including children, radios, food and beverage consumption and occurrences outside the vehicles.
The first part of that study, released in May, showed cell phones to be just one of numerous non-driving activities that can lead to accidents.
Note: Reinfurt can be reached at 919-962-8719 or donald_reinfurt@unc.edu for a copy of his report.