Citation

Liu C, Subramanian R. NHTSA, National Center for Statistics and Analysis. Washington, D.C.: U.S. Department of Transportation, National Highway Traffic Safety Administration, 2020.

Copyright

(Copyright 2020, NHTSA, National Center for Statistics and Analysis)

The full document is available online.

Abstract

This study examines the relationship between passenger vehicle occupant injury severity outcomes and the vehicle age or model year (MY) in police-reported crashes. It shows that occupants of older model year vehicles and higher vehicle age had a higher percentage of occupants who were severely injured. The study uses both univariate descriptive analysis and statistical modeling that adjusts for other confounding factors.

When examining the role of vehicle age, the univariate descriptive analysis shows that among all passenger vehicle (passenger cars, SUVs, pickup trucks, or vans) occupants involved in police-reported crashes, the percentages of occupants who were severely injured was: 1.20 percent/1.60 percent/1.89 percent/2.20 percent for vehicle age groups 1-6 years/7-11 years/12-15 years/>15 years, respectively. Also, the percentages of occupants who were severely injured, when examining by vehicle model year, were: 3.09 percent/2.50 percent/1.65 percent/1.08 percent for vehicle model year groups MY 1987 and earlier/MY 1988-1994/MY 1995-2011/MY 2012-2018, respectively.

After adjusting for many occupant, vehicular, and crash factors, the multivariate regression model analysis shows the similar results that when compared to the baseline of a vehicle 1 to 6 years old, that the odds of severe injury is 1.11 times for occupants of vehicles 7 to 11 years old, 1.19 times for occupants of vehicles 12 to 15 years old, and 1.23 times for vehicles older than 15 years. Also, when compared to the baseline of a vehicle in MY 2012-2018, the results have shown that the odds of severe injury is 1.15 times for occupants of vehicles in MY 1995-2011, 1.28 times for occupants of vehicles in MY 1988-1994, and 1.50 times for vehicles in MY 1987 and older.

This study uses NHTSA's National Automotive Sampling System General Estimates System (NASS-GES) 2012-2015 data as well as the 2016-2017 data from the replacement system in 2016 – the Crash Report Sampling System (CRSS).