The objective of this observational, before and after study among all teens in Pennsylvania who turned 16 in 1999 or 2000 and obtained a license within 17 months of their 16th birthday, was to assess the effect of a new graduated driver licensing (GDL) system on 16 year olds' licensing behavior. A 3-phase GDL system was in place during the entire study period, including a learner permit (LP) phase (attained at age 16 after passing a written exam), a junior license phase (attained after passing a driving exam), and a regular license phase. In January 2000, Pennsylvania increased the mandatory LP phase from a minimum of 30 days to 180 days. There was no change to the written or driving exams during this period. Using the state driver licensing database, subjects who turned 16 in 1999 were compared with those who turned 16 in 2000 for how long it took to obtain a LP and how long they held the LP before obtaining a junior license. Teens who turned 16 in 1999 (n = 30,642) took a mean of 55 days to take and successfully pass a written exam to obtain their LP, compared with a mean of 18 days for those who turned 16 in 2000 (n = 21,846) (sig. at p < 0.0001). Although the mandatory minimum LP phase was 30 days in 1999, 16 year olds, on average, stayed in this phase for 81 days. In 2000, when the mandatory minimum LP phase was 180 days, 16 year olds, on average, stayed in this phase for 199 days. The total time it took 16 year olds to obtain the junior license increased from a mean of 136 days in 1999 to 217 days in 2000 (sig. at p < 0.0001). 16 year olds adapted to the new GDL system in Pennsylvania by modifying their behavior. Following implementation of the new system, teens took less time to obtain their learner's permit. They also moved out of the LP phase more quickly, after the minimum time period elapsed. Despite these changes, Pennsylvania was effective in prolonging the overall length of supervised driving by imposing a mandatory 6-month LP phase. (Author/publisher)
Abstract