Enlarge / You should not do this while you are driving. (credit: Getty Images)

Distracted driving isn't only a result of drivers using their phones when they should be paying attention. But it is a significant cause of the problem, accounting for at least 13 percent of distracted driving deaths and rising to 1 in 5 for young drivers. Now, a study conducted with customers of the Progressive insurance company has tested different strategies to get those drivers to put their phones down in the car, and it found two that significantly reduced handheld use, with the effect persisting after the end of the study.

The study recruited 1,653 customers already enrolled in its Progressive Snapshot program, which involves the use of a smartphone app that detects phone use while driving. Before the start of the trial, the participants all averaged more than 6.4 minutes per hour of handheld use while driving—Progressive says its safest customers have handheld usage of less than 1 minute per hour while driving.

Five test groups

The drivers were split into five different arms, each with increasing amounts of intervention. The first group just received education about the problem, such as statistics about state laws that ban phone use while driving, increased crash risks, and recommendations to use hands-free options like a phone mount or casting interface instead.