Small incentives drive lasting seatbelt habits, cut unbuckled trips by a third

When drivers were promised a share of $125 weekly prize money for maintaining perfect seatbelt use streaks, they established long-lasting habits, according to research from the Perelman School of Medicine at the University of Pennsylvania, published in the American Journal of Public Health. Driving without a seatbelt decreased 26% relative to the control during the incentive program and was 33% less than the control even after the program ended. 

The shared prize approach outperformed two other approaches: one that promised a weekly lottery entry for the full $125 prize for maintaining a streak, and another that texted drivers personalized feedback on their buckling habits. The study, involving more than 1,100 drivers from 49 states, is among the first to demonstrate that using connected vehicle data to provide feedback to drivers can encourage more consistent seatbelt use in a large, national population.

“We know that seatbelts reduce serious crash-related injuries and death by about half,” said lead author Jeff Ebert, director of Applied Behavioral Science at the Penn Medicine Nudge Unit, which tests small behavioral science-informed interventions to encourage positive changes in behavior. “About 3,000 lives could be saved each year in the United States if everyone wore seatbelts. If this ‘nudge’ combined with incentives could be scaled up, our results show it could lead to a substantial reduction in driving without seatbelts. Even a 25 percent decrease in unbuckled trips would mean about 750 more people going home to their families every year.”

Participants in the study who were promised a weekly share of a $125 pot for achieving a perfect streak—using their seatbelts every time they drove their car more than a tenth of a mile—drove unbuckled 8.7% of the time. The group that was given a chance to win $125 in a lottery among their fellow participants drove unbuckled 10.5% of the time. And the group that only received text message feedback on their seatbelt habits drove unbuckled 10.6% of the time. A control group, which didn’t get feedback or incentives, drove unbuckled 11.9% of the time.

In a five-week follow-up after the interventions ceased, the shared prize group maintained a lower rate of unbuckled trips (8.0%) compared to the control group (11.7%), representing a 33% relative reduction—even without a monetary incentive on the line. The group receiving feedback texts also saw a reduction in unbuckled trips (9.8%), while the lottery group’s rate (10.4%) was statistically similar to the control group.

In addition to seatbelt use, the researchers also measured handheld phone use while driving among a smaller sample of the participants. Distracted driving contributes to more than 3,000 deaths each year, with 12 percent including incidence of cell phone use. Participants offered a shared pot incentive for perfect phone-free streaks had a minute less handheld phone use per hour of driving (2 minutes 47 seconds per hour) than the control group (3 minutes 49 seconds per hour); this difference wasn’t statistically significant in the smaller sample.

“Tying incentives to perfect streaks worked really well for buckling up—a simple, one-click behavior that most drivers already perform, but sometimes forget,” said M. Kit Delgado, faculty director of the Penn Medicine Nudge Unit and an associate professor of Emergency Medicine and Epidemiology. “For behaviors like reducing handheld phone use, which require more effort to change, we’ve found in prior studies that rewarding step-by-step improvements can be a more effective long-term strategy, especially among high-risk drivers.”

Read more at Penn Medicine News.