UW News

March 11, 2010

UW research team finds one in 16 Seattle drivers yakkin’ on the phone

A recent University of Washington study found one driver in 16, or about 6 percent, uses a mobile phone while driving on Seattle streets.

Philip Howard, a UW associate professor of communication, directed a team of undergraduates who observed more than 2,460 drivers using cell phones from Feb. 12 to 28. Each driver had one hand on the wheel and a mobile phone in the other. Some drivers were making calls; others were texting or otherwise using their phones.

Cell phone use peaked on Thursdays, Fridays and during afternoon rush hour, when the ratio was one in 13.

Fifty-five percent of drivers using mobile phones were male, 45 percent female. Some 30 percent of drivers using phones appeared to be under 25, and in that group, the percentages reversed: females outnumbered males 57 percent to 43 percent.

Researchers stood at 47 randomly selected major and minor intersections around the city, noting phone use, gender and whether the driver appeared to be 25 or under.

The research, an audit study because actual behavior was systematically observed, was conducted by more than 90 UW students on arterial routes. The students chose random times between 8 a.m. and 9 p.m. In all, they observed 39,787 Seattle drivers.

The study came after a measure the Washington state Senate passed Feb. 5 that would have made it a primary offense to hold a cell phone to one’s ear while driving, reading, writing or text messaging.

The measure would have strengthened the state’s secondary-offense law, which allows police to add an extra fine if the driver is pulled over for another offense such as speeding.

On March 3, however, the House rejected the Senate’s measure, instead approving a ban on texting and cell phone use among teenage drivers.


Washington is one of six states and the District of Columbia to have passed laws regulating cell phone use while driving but is the only state that considers phoning without a hands-free device a secondary offense.

“We wanted to do this study because there has been a lot of talk about driver safety and mobile phone use,” said Howard. “We always notice drivers around us who are talking on the phone and not paying attention to the road. We wanted to find out how many people were doing just that.”

Many studies document ways cell phones distract drivers, but there have been comparatively few scientific studies to estimate the number of drivers using phones, according to Howard.

A national study conducted in 2006 found proportions of cell phone use similar to those noted in Seattle.

“It is hard to say if laws on cell phone driving have had much impact so far,” said Edwin Ortiz, a senior history major who is one of the student researchers. “There are a lot more mobile phone users now than in 2006, and a lot more media attention to accidents caused by cell phone drivers, but the rate of use is still high.”

As additional field observations, the student researchers noted that drivers who used cell phones were almost always alone in their cars. Drivers who were seen texting and clearly distracted from the road were recorded as using cell phones. Some drivers initiated a task with their cell phone at a stop light but ended when the light turned green. Other drivers were impressive multitaskers. They combined various activities: eating, smoking, using cell phones, driving with pets in laps or putting on makeup.

When the study was finished, the 90 students were asked about their own use of cell phones. More than two thirds reported that they regularly use their phones while driving.

For the complete study, go to www.com.washington.edu.

###

For more information, contact Howard at 206-612-9911 or pnhoward@uw.edu; Ortiz at 425-772-1174 or edlortiz@u.washington.edu.