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Is seat belt usage by front seat passengers related to seat belt usage by their drivers?
Shashi S Nambisan1, Vinod Vasudevan
1Center for Transportation Research and Education, Professor of Civil Engineering, Iowa State University, 2711 S. Loop Drive, Suite 4700, Ames, IA, 50010-8664, USA. shashi@iastate.edu
Introduction:
Unrestrained drivers and passengers are involved in a significant amount of fatalities and injuries in motor-vehicle crashes in the United States. While the literature documents the effectiveness of seat belt usage in reducing crash outcomes, such as fatalities and the severity of injuries, there is a need to evaluate the impact of seat belt usage by drivers and passengers in their respective vehicles. These findings could help develop effective education and enforcement strategies to enhance occupant safety.
Method:
This paper summarizes a study comparing seat belt usage rates of drivers and passengers based on whether or not the driver uses a seat belt. Observational data from 50 sites in the state of Nevada over 3 years are used for analyses. The data are stratified based on the gender of the driver and passengers in the front seat of the vehicle and are based on area type (rural or urban).
Results:
A comparison of the rates of seat belt usage across for the aggregated data and for various types of disaggregation and statistical analyses to compare the rates of seat belt use among passengers based on the use of seat belts by drivers confirms that when drivers use seat belts, their respective passengers are much more likely to use seat belts. Further, if drivers do not use seat belts, their passengers are not likely to use seat belts. This observation is comparable for male drivers and female drivers, and also for male passengers and female passengers. Further, there are no differences for combinations of the genders of the drivers and passenger (i.e., both male or female, or one male and one female).
Impact On Industry:
These results suggest that education and enforcement strategies would benefit most by working toward increasing seat belt usage rates among drivers.
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