Background: Seat belt use is an effective way to reduce the morbidity and mortality of motor vehicle crashes. However, 1 in 10 adults do not always wear a seat belt, with the lowest use rates of seat belt use among young adults. Digital behavioral interventions could be useful to increase seat belt use, but remain under-developed. This randomized clinical trial tested the efficacy of a 6-week behavioral text message program promoting seat belt use among young adults. Methods: A parallel, 2-group, single-blind, individually randomized clinical trial. Eligible individuals recruited from 4 Emergency Departments were aged 18 to 25 years who reported driving or being a passenger without always using a seat belt in the past 2-weeks. Two hundred eighteen participants completed the 2-week trial run-in phase were randomly assigned 1:1 to intervention: self-monitoring control. The intervention arm (n=110) received SaVE , a 6-week automated interactive text message program including weekly seat belt use queries with feedback and goal support to promote consistent use of a seat belt. The control arm (n=108) received identical weekly seat belt use queries but no additional feedback. The primary and secondary outcomes were the proportion of young adults reporting always wearing a seat belt at 6- and 12-weeks, collected via web-based self-assessments and analyzed under intent-to-treat models. Results: The mean (SD) age was 21.5 (2.2) years, 137 (63%) were female, 110 (50%) were White, and 33 (15%) were Hispanic. The 6-week follow-up rate was 86.2% (n=187), with no differential attrition. At 6-weeks, 39.1% (95% CI, 30.0%-48.9%) of intervention participants always wore a seat belt vs. 23.1% (95% CI, 15.6%-32.2%) of control participants (odds ratio, 2.13; 95% CI, 1.18-3.84; P =.01). The 12-week follow-up rate was 64.2% (n=140), with no differential attrition. At 12 weeks, 42.7% (95% CI, 15.6%-32.2%) of intervention participants always wore a seatbelt vs. 32.3% (95% CI, 20.6%-44.0%) of control participants (odds ratio, 1.25; 95% CI, 0.67-2.31; P =.48). Conclusions: Results of this randomized clinical trial demonstrated that an interactive text message intervention using goal support was more effective at promoting seat belt use among targeted young adults than self-monitoring at 6-weeks. These findings, if replicated, suggest a scalable approach to help improve seat belt use and reduce crash-related morbidity and mortality.
Effectiveness of a text message intervention promoting seat belt use among targeted young adults: A randomized trial