In Washington state's first study to examine driver use of electronic devices, UW investigators saw that more than 8 percent of drivers were engaging with such devices behind the wheel, higher than previously estimated. Among those driving distracted, nearly half (45 percent) were observed texting.
The study looked at the behaviors of 7,800 drivers in six counties. Using randomized observations at controlled intersections, investigators recorded drivers engaged in a range of distracting activities, including texting and talking on the phone.
Researchers found that the most common source of distraction was a hand-held device, such as a cell phone. Among the 3.4 percent of drivers who were talking on a hand-held phone, half were holding the device near or under the steering wheel. This risky behavior diverts the driver's attention from the road.
The study has important implications for state public health and law enforcement officials. Motor vehicle injuries remain the leading cause of death for Americans under 35 years of age. Estimates suggest that up to 28 percent of crash risk is attributable to cell phone use or text messaging in vehicles. While the use of cell phones in the United States has grown exponentially, enforcement of distracted driving laws has struggled to keep pace.
"These findings suggest that distracted driving is more common than we thought and that texting has become a major cause of distraction," said Dr. Beth Ebel, principal investigator with UW Medicine's Harborview Injury Prevention and Research Center and UW associate professor of pediatrics. "Most people support laws restricting texting and cell phone use in vehicles, yet some choose to engage in behaviors that put everyone on the road at risk."
"These traumatic injuries are entirely preventable," added Ebel. She noted that prior studies show texting while driving increases crash risk by 23 times, similar to driving with a blood alcohol level of 0.19.
In 2010, Washington state adopted a primary enforcement law for hand-held mobile devices and text messaging with an imposed fine of $124. The rise in distracted driving is prompting greater attention from law enforcement. In a recent King County seat belt citation campaign, more tickets were issued for cell phone use and texting than for not wearing a seat belt.
"Otherwise responsible drivers who talk or text have caused collisions that kill or seriously injure others. These drivers are criminally prosecuted, just like other impaired drivers," said Amy Freedheim, senior deputy prosecuting attorney at the King County Prosecuting Attorney's Office.
The data released today are preliminary results, part of a broader study conducted to explore the effects of law enforcement on electronic distracted driving. In October, investigators will release a statewide report card providing more data by county. This baseline assessment will help county law enforcement, prosecutors and public health officials evaluate the effectiveness of various ways to stop distract driving. If intervention strategies are effective, traffic safety experts hope that a successful model can be adapted in other states.
"The recent findings provide objective support for what we've long believed: texting contributes to more collisions than we can prove," said Chief John R. Batiste of the Washington State Patrol. "After a collision, drivers almost never admit they were texting. We believe the problem has, until now, been drastically under-reported."
Explore further: Review: Paperless society remains a distant dream