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OBJECTIVES: To analyse factors influencing the American public's preferences for changes to teenage driver licensing requirements. METHODS: We employed a discrete choice experiment (DCE) with 808 participants from National Opinion Research Center's AmeriSpeak panel to assess preferences for two existing elements (on-road testing and intermediate licensure period) and a new feature (driver monitoring with telematics during the intermediate licensure period) of licensing system. Multinomial and mixed logit models were used to estimate preference weights, marginal rates of substitution and the relative importance of each attribute. RESULTS: Among 730 respondents who completed all DCE choice tasks, we found robust support for changes to teenage driver licensing requirements, with preferences varying by individual characteristics. Respondents expressed a high baseline support for changes to teen driving licensure policies. They favoured testing, prioritising easy tests and opposed prolonged driver monitoring and extended intermediate licensure periods. Baseline preference weights exhibited substantial heterogeneity, emphasising the diversity of public preferences. The marginal rates of substitution revealed a preference for extended driver monitoring over an extended intermediate licensure period. An easy test was valued at 2.85 times more than a hard one. The most influential attributes were the length of intermediate licence period and testing requirements, with the former twice as important. CONCLUSIONS: Our study found robust support for reforms to teenage driver licensing requirements, favouring easier on-road driving tests over an extended period of intermediate licensure and driver monitoring. Public preferences for licensing systems need to be balanced with the broader policy objectives including optimising mobility and maximising safety.
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BACKGROUND: Most studies evaluating the effectiveness of Graduated Driver Licensing (GDL) have focused on the overall system. Studies examining individual components have rarely accounted for the confounding of multiple, simultaneously implemented components. The purpose of this paper is to quantify the effects of a required learner license duration and required hours of supervised driving on teen driver fatal crashes. METHODS: States that introduced a single GDL component independent of any other during the period 1990-2009 were identified. Monthly and quarterly fatal crash rates per 100,000 population of 16- and 17-year-old drivers were analyzed using single-state time series analysis, adjusting for adult crash rates and gasoline prices. Using the parameter estimates from each state's time series model, the pooled effect of each GDL component on 16- and 17-year-old drivers' fatal crashes was estimated using a random effects meta-analytic model to combine findings across states. RESULTS: In three states, a six-month minimum learner license duration was associated with a significant decline in combined 16- and 17-year-old drivers' fatal crash rates. The pooled effect of the minimum learner license duration across all states in the sample was associated with a significant change in combined 16- and 17-year-old driver fatal crash rates of -.07 (95% Confidence Interval [CI] -.11, -.03). Following the introduction of 30 h of required supervised driving in one state, novice drivers' fatal crash rates increased 35%. The pooled effect across all states in the study sample of having a supervised driving hour requirement was not significantly different from zero (.04, 95% CI -.15, .22). CONCLUSION: These findings suggest that a learner license duration of at least six-months may be necessary to achieve a significant decline in teen drivers' fatal crash rates. Evidence of the effect of required hours of supervised driving on teen drivers' fatal crash rates was mixed.