Graduated driver licensing (GDL), as introduced in New Zealand in 1987, included three main driving restrictions: a night-time curfew (10pm-5am), no carrying of young passengers, and a blood alcohol limit of 30mg/100ml of blood. The aim of the present study was to determine the impact that these restrictions had on young driver crashes. For this study the New Zealand Police traffic crash reports were linked to the national hospital inpatient records (1980-1995). Multivariate binomial regression was used to compare car crashes involving a young driver licensed before the GDL (pre-GDL, n=2252) with each of the graduated licence groups: full GDL (n=1273); restricted licence (n=980); or learner licence (n=399). The results showed that, compared to the pre-GDL group, restricted licence drivers had fewer crashes at night (p=0.024), fewer involving passengers of all ages (p=0.034), but did not differ where alcohol was suspected. The learner licence drivers had a higher proportion involving passengers (p=0.023), but night-time and alcohol suspected crashes did not differ. The full GDL drivers did not differ significantly from the pre-GDL drivers for any of the factors examined. These results suggest that the graduated driver licensing restrictions, especially the night-time curfew, have contributed to a reduction in crashes involving young drivers. Particularly encouraging were the results for the restricted licence drivers who are the licence group most affected by the restrictions.
Abstract