Effects of graduated driver licensing on licensure and traffic injury rates in Upstate New York

Abstract

Objective In 2003, New York State implemented an enhanced graduated driving licensing (GDL) program that requires extended supervised driving and a passenger restriction. This study examines its safety benefit in 55 Upstate New York counties. Methods We analyzed fatal/incapacitating traffic injury data among 16-, 17- and 21–24-year olds for the years 2001 and 2005 using the negative binomial model. To adjust for trends in the traffic injury rate, the relative rate ratio (rRR) of 16- and 17-year olds relative to 21–24-year olds was estimated. Results GDL implementation was associated with a 31% reduction in the driver injury rate (rRR 0.69, 95% confidence interval (CI) 0.49–0.96), but not with any statistically significant change in the passenger injury rate (rRR 1.19, 95% CI 0.77–1.84), or pedestrian and bicyclist injury rate (rRR 1.53, 95% CI 0.89–2.62) among 16-year olds. Sixteen-year olds experienced a 21% decline in licensure rates between 2001 and 2005. GDL implementation had no appreciable impact on driver injury and licensure rates for 17- and 21–24-year olds. Conclusions GDL implementation is associated with a significant reduction in licensure and driver injury rate among 16-year olds. GDL implementation does not have a statistically significant impact on passenger, pedestrian, and bicyclist injury rates for 16-year olds.