A recent Proceedings of the National Academy of Sciences study evaluates the effectiveness of behavioral interventions to reduce distracted driving.
Study: A randomized trial of behavioral interventions yielding sustained reductions in distracted driving. Image Credit: Andrey_Popov / Shutterstock.com
Risks involved in distracted driving
In the United States, over 3,000 deaths and 400,000 injuries occur each year due to distracted driving. A significant number of distracted driving cases has been attributed to phone use by drivers between the ages of 15 and 24 years.
Naturalistic studies have shown that all phone use is not equally risky. Although both handheld and hands-free phone use promotes cognitive distraction, handheld phone use is associated with greater visual and physical distraction. Researchers estimate that handheld phone use increases the risk of accidents by 2-12%, whereas hand-free phone use does not appear to increase the risk of a crash.
Considering these findings, lawmakers in 27 U.S. states have banned the use of handheld phones while driving. Implementation of this rule has been challenging, as some drivers adopted riskier approaches to evade detection, such as holding the phone lower during use.
Usage-based insurance (UBI) policies have shown positive effects in reducing hand-held phone use while driving. This program evaluates a driver’s handheld phone use and other risky driving behaviors for one month. The driver’s upcoming policy is estimated based on the predicted risk of a crash.
Thus, UBI provides an incentive to drivers to reduce their use of handheld phones while driving. In fact, one recent study revealed that UBI promoted 23% less hand-held phone use; however, this change in behavior was not sustained for a prolonged period.
About the study
The current randomized control trial (RCT) evaluated interventions designed to promote more sustained behavior changes to prevent distracted driving. These interventions encouraged drivers to exert situational self-control by removing temptations and replacing handheld phones with less risky hands-free alternatives. The intervention period was extended to ten weeks to provide more time for the participants to develop their new habits.
The current study recruited customers of Snapshot, an auto insurance program, and randomly assigned them to one of five study arms. All five study groups were educated about the risks of handheld phones.
The control group only received information about how handheld phone use makes driving less safe, whereas arm two received a free phone mount. Arm three received an additional commitment exercise and habit formation tips three times each week for the first two weeks and once every week for the remaining eight weeks.
Arm four and five participants received additional text messages indicating their handheld phone use goal for the new week and whether they met their goal for the previous week. These goals were gamified with the potential to earn or lose points.
Arm five participants who met their weekly goals and successfully completed a week's intervention period at a platinum level of 170 points or more received an equal share of a $2,000 prize.
Study findings
A total of 1,653 eligible participants were randomly assigned to the five study arms. Of these, 1,436 completed a survey questionnaire. The mean age of the study cohort was 32.8 years, and 66.5% of them were female.
Study participants provided a phone mount or commitment exercise did not exhibit any reduction in handheld phone use while driving. However, weekly gamified goals and social competition led to a significant decrease in handheld phone use while driving, thus indicating the importance of performance feedback for behavior change.
Financial incentives led to the greatest reduction in handheld phone use. More specifically, study participants who won financial incentives as a part of meeting and completing weekly goals exhibited a 28% decrease in handheld phone use as compared to the control group.
Study participants who received performance feedback or a combination of feedback and incentives exhibited sustained reductions in handheld phone use even after the feedback and incentives were no longer provided.
Conclusions
Behavioral interventions that involve gamified goals and social competition reduced the use of handheld phones while driving. The incorporation of financial incentives further reduced handheld phone use, which could significantly prevent crashes.
The study findings revealed that drivers developed a habit of not using handheld phones while driving, even beyond the study period. In the U.S. alone, this strategy could result in two billion fewer hours of distracted driving every year.
Journal reference:
- Ebert, J. P., Xiong, R. A., Khan, N., et al. (2024) A randomized trial of behavioral interventions yielding sustained reductions in distracted driving. Proceedings of the National Academy of Sciences 121(32); e2320603121. doi:10.1073/pnas.2320603121