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

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.