The study finds that in a world where motorists are distracted by everything from cell phones to screaming children, billboards aren't any more distracting than other signs or even bare landscapes. The presence of billboards don't cause any measurable difference in driving behavior, according to the study conducted by the Virginia Tech Transportation Institute for the Foundation for Outdoor Advertising Research and Education.
"The presence of a billboard does not cause a measurable change in driver behavior in terms of usual behavior, speed maintenance, or lane keeping," said Suzanne E. Lee, the study's principal investigator at the Blacksburg, Va., university.
Virginia Tech recruited 36 motorists who drove a specially outfitted car on a 35-mile stretch in Charlotte, N.C. The route included highways and secondary roads, a typical mix of urban and suburban landscapes. There were 30 billboards of varying sizes on one or both sides of the road. The motorists drove a car fitted with cameras to measure eye glances to the tenth of a second (10,895) and the 97,580 pieces of data in 54 hours of vehicle speed and lane position.
"Bottom line, there was no difference," said Charlie Lamarr, chairman of the Foundation for Outdoor Advertising Research and Education.
For the outdoor industry, the study confirms what they've been saying all along: There's no safety issue, even though that's sometimes trotted out as an argument against placing a billboard in a certain spot. The Virginia Tech team came up empty when they searched for previous research on the topic. Lee said a review found that there's no federal traffic safety data on accidents linked to drivers distracted by bulletin boards.
A 2003 study by Virginia Commonwealth University found that of 2,000 crashes linked to driver distraction, none were caused by bulletin boards themselves. Twenty-five were attributed to traffic signs and only one was connected to a motorist being distracted by a billboard under repair. Lamarr, who used to be general counsel of Lamarr Advertising in Baton Rouge, La., recalls the industry doing only smaller studies on safety.
"There's no significant link to accidents or traffic safety problems, but as far as I know, there's no really empirical study like this," Lamarr said.
The study involved only static billboards, with the exception of two variable message boards. No work was done with glitzy electronic billboards, although a separate Canadian research group has been studying them under different conditions and methodology.
Using the cameras, the Virginia Tech researchers studied motorists' glances, average duration and total glances, not only for billboards but also other things like logo and business signs, as well as places where there are no signs or buildings to distract driving. The motorists didn't exhibit different visual behavior when passing either billboards or the other signs; only two times did the results from billboards and non-distracting landscapes differ. Speed and lane changing didn't differ between the three categories.
"The fact that a driver looks at a billboard doesn't mean that he's distracted from a safety point of view," Lamarr said. "Drivers look at a lot of things outside of the car, all the time: Cars and people and trees and buildings and billboards. This study shows that like many other things that people look at, billboards are not inherently distracting from the act of driving a car."
In what might be a dead end in the study, only 25 percent of drivers said they noticed billboards along the way. The question was one of a number answered by the motorists, who weren't aware that the study was testing their reactions to billboards. Lee cautions not to read too much into the responses, as researchers gave the participants 30 choices and asked the drivers to check off the top five items that caught their attention. Billboards competed with traffic, road signs, other drivers, landscapes, emergency vehicles, restaurants, pedestrians and hotels/motels, among others.
Lamarr rejects that the answers have any bearing on the effectiveness of outdoor advertising, which has been proven in several past and present studies that are designed specifically for effectiveness. Lee said she didn't conduct a marketing study and those results shouldn't be counted as such.
"This study wasn't designed, nor does it show the effectiveness of outdoor advertising. It was simply designed to show the impact of outdoor advertising in driver performance," said Lamarr. "The fact that drivers are not distracted from their task of driving, as shown by lane movements or speed variations, does not mean that either the drivers do not see the billboards or that the billboards do not have any impact on the drivers."
The study is part of a renewed effort by the foundation, which dates back to the 1930s but was rechartered in 1999. The foundation awards scholarships but has been sponsoring a handful of studies like this one to research topics of interest to the outdoor industry.