Risk and Protective Factors for Injury in Adult Front- and Rear-Seated Motor Vehicle Occupants in New York State

Abstract

Although seatbelt use is known to reduce motor vehicle occupant crash injury and death, rear-seated adult occupants are less likely to use restraints. This study examines risk and protective factors associated with injury severity in front- and rear-seated adults involved in a motor vehicle crash in New York State. The Crash Outcome Data Evaluation System (CODES) (2016-2017) was used to examine injury severity in front- and rear-seated occupants aged 18 years or older (N = 958,704) involved in a motor vehicle crash. CODES uses probabilistic linkage of New York State hospitalization, emergency department, and police and motorist crash reports. Multivariable logistic regression models with MI analyze employed SAS 9.4. Odds ratios are reported as OR with 95% CI. The mortality rate was approximately 1.5 times higher for rear-seated than front-seated occupants (136.60 vs. 92.45 per 100,000), with rear-seated occupants more frequently unrestrained than front-seated occupants (15.28% vs. 1.70%, p < 0.0001). In adjusted analyses that did not include restraint status, serious injury/death was higher in rear-seated compared to front-seated occupants (OR:1.272, 1.146-1.412), but lower once restraint use was added (OR: 0.851, 0.771-0.939). Unrestrained rear-seated occupants exhibited higher serious injury/death than restrained front-seated occupants. Unrestrained teens aged 18-19 years old exhibit mortality per 100,000 occupants that is more similar to that of the oldest two age groups than to other young and middle-aged adults. Speeding, a drinking driver, and older vehicles were among the independent predictors of serious injury/death. Unrestrained rear-seated adult occupants exhibit higher severe injury/death than restrained front-seated occupants. When restrained, rear-seated occupants are less likely to be seriously injured than restrained front-seated occupants.

Keywords: injury severity; motor vehicle crash; rear-seated adults; restraint use.

Figure 1

(a) Percent of front- and rear-seated occupants involved in a motor vehicle crash who had no or minor injury, stratified by restraint status. (b) Percent of front- and rear-seated occupants involved in a motor vehicle crash who had moderate or severe injury, stratified by restraint status. (c) Percent of front- and rear-seated occupants involved in a motor vehicle crash who sustained a fatal injury, stratified by restraint status.

Figure 1

(a) Percent of front- and rear-seated occupants involved in a motor vehicle crash who had no or minor injury, stratified by restraint status. (b) Percent of front- and rear-seated occupants involved in a motor vehicle crash who had moderate or severe injury, stratified by restraint status. (c) Percent of front- and rear-seated occupants involved in a motor vehicle crash who sustained a fatal injury, stratified by restraint status.

Figure 2

(a) Percent mortality of front- and rear-seated occupants involved in head-on crashes. (b) Percent mortality of front- and rear-seated occupants involved in rear-end crashes.