Highway death toll signs may cause more crashes

Have you seen those highway message boards that display crash death totals? A recent study of some in one state found that more vehicle crashes occurred within a few miles of the signage, suggesting that the “in-your-face” approach may be a distraction to drivers.

The study focused on crash data from Texas, where death toll messages were displayed for a week each month by the state’s Department of Transportation. Researchers from the University of Minnesota and the University of Toronto looked at the periods before the messaging campaign (January 2010-July 2012) and after it was launched (August 2012-December 2017).

They compared weekly differences within each month, and found that more crashes occurred during the weeks the fatality messages appeared than the weeks they didn’t. Specifically, within 6.2 miles after the message board, the number of crashes increased 4.5%. The messages also were linked to an increase in the number of multi-vehicle crashes. Overall, the researchers say the fatality messages cause an additional 2,600 crashes and 16 deaths a year in Texas.

The researchers suggest that the messaging approach affects drivers’ cognitive load, causing distraction and temporarily affecting their ability to respond to changing traffic conditions.

“Distracted driving is dangerous driving,” said researcher Joshua Madsen, an assistant professor at U of M. “Perhaps these campaigns can be reimagined to reach drivers in a safer way, such as when they are stopped at an intersection, so that their attention while driving remains focused on the roads.”

Previous research shows that short, quirky digital highway messages, such as “Get your head out of your apps” and “Mom needs your hug not your text,” are perceived by drivers as memorable and relatively effective.

The new study was published online in the journal Science.