A new study suggests that digital highway signs that are designed to encourage safe driving contribute to an increase in nearby traffic accidents.
The study, published in April 2022 by the American Association for the Advancement of Science on science.org, looked at several years of data from Texas to find that the number of vehicle crashes increased by an average of 4.5% in the 6.2 miles following signs displaying year-to-date road fatality statistics. Although these signs were meant to encourage safe driving, the research suggests that they have an opposite, distracting effect.
“When you’re on the road, your eyes belong on the road. Signs that take your attention away from the road and break your concentration are going to cause distracted driving and accidents, no matter what message they’re trying to convey,” said Scenic America President Mark Falzone. “This study just adds to the body of research telling us that digital signs including billboards are traffic safety hazards that don’t belong on our roadways.”
For this study, researchers examined Texas highway crash data between August 2012 and December 2017. During this time, the Texas Department of Transportation (TxDOT) displayed messages on these signs reporting year-to-date highway fatalities as a means of encouraging safe driving. The signs appeared to have an opposite effect; the study authors noted an increase in accidents downstream of these signs during the weeks when such messaging was presented. In reviewing the data, the researchers found no difference in results when controlling for time of day, weather, vehicle type, driver age group, driver gender, and other variables.
The researchers concluded that the fatality messages caused an additional 2,600 crashes and 16 deaths for year, costing about $380 million each year. By applying this anticipated trend across the 28 states that used such messaging, the impact of this messaging platform and tactic multiplies. According to the National Highway Traffic Safety Administration, nearly 39,000 Americans died in traffic accidents in 2020, the highest number since 2007.
In 2021, the Federal Highway Administration determined that displaying traffic fatality statistics was not an appropriate use of these electronic messaging signs. The FHWA outlined acceptable uses for these signs, such as alerting travelers to traffic conditions and relevant, real-time travel information.
“Signs and digital billboards like these with changing messages serve one purpose: to catch drivers’ attention, which contributes to distracted driving, traffic accidents, and deaths. We’ve seen studies from Alabama, Florida, and around the world, and they all point to same conclusions,” added Falzone. “Any state or city that wants to add more signs to its roadways needs to take these risks very seriously.”