Estimating the effect of the vehicle model year on crash and injury involvement

The study was designed to investigate the effect of the model year on crashes and injuries, where the latter were of the mild to moderate variety, independent of other driver or vehicle factors and travel exposure. Previous research on vehicle safety design has focused on fatal or serious injuries but, for traffic safety evaluations in smaller jurisdictions and over limited time frames, a more numerous-outcome variable must be used. The study was conducted with over 32 000 driver-vehicle combinations. Binary logistic regression was employed to estimate the effects of the model year ranges on injuries and driving exposure, while controlling the other factors. A salutory effect of increasing the model year on the injury risk was found but this was countered by the increased travel associated with the newer vehicles.