McCartt, Anne T.; Teoh, Eric R.
Insurance Institute for Highway Safety
To determine U.S. teenagers’ current crash involvement rates as well as changes in crash rates since 1996, when the first graduated driver licensing (GDL) program was implemented.Methods:
Data were extracted for fatal crashes from the Fatality Analysis Reporting System and for police-reported crashes from the National Automotive Sampling System General Estimates System. To calculate crash rates, population data were obtained from the Census Bureau and mileage data were obtained from the 1995-96, 2001-02, and 2008 National Household Travel Surveys. Analyses focused on differences between teenage drivers ages 16-19 and middle-aged drivers ages 30-59.Results:
Per mile traveled, rates of fatal crashes and police-reported crashes in 2008 were much higher for teenagers than for middle-aged drivers, and much higher for 16-17 year-olds than for older teenagers. Per capita rates of fatal and police-reported crashes in 2012 were lower for 16 year-olds than for middle-aged drivers, whereas rates for older teenagers, especially 18-19 year-olds, were higher. From 1996 to 2012, there was a steady, steep decline in per capita fatal and police-reported crash involvement rates for teenagers. The largest declines occurred among younger teenagers, the ages most directly affected by GDL, but all teenagers had much larger declines than middle-aged drivers. Substantial declines also occurred in teenagers’ per mile traveled rates of fatal and police-reported crashes from 1995-96 to 2008. Declines generally were larger than those for middle-aged drivers, not always consistent across time, and sometimes larger for older teenagers than for younger teenagers. Declines occurred between 1996 and 2012 in the proportion of younger teenagers’ fatal crash involvements occurring at night and with two or more teenage passengers, whereas there were either increases or smaller decreases among older teenagers and middle-aged drivers. This is consistent with the implementation of nighttime and passenger restrictions for intermediate driver’s licenses in almost all states during the study period. The proportion of fatally injured teenage drivers with positive blood alcohol concentrations declined, whereas the proportion changed little for middle-aged drivers. The proportion of teenage drivers in fatal crashes with driver errors declined, although less so than for middle-aged drivers. The percentage of fatal crash involvements involving speeding increased among 16 year-olds, whereas the percentage decreased slightly among other teenagers and increased slightly among middle-aged drivers.Conclusions:
Substantial reductions occurred in fatal and nonfatal crash risk among teenage drivers during the period of implementation of GDL laws across the United States. Per capita crash reductions were especially large for 16-17 year-olds, but substantial declines in per capita and per mile traveled rates occurred for all teenagers. However, teenagers’ crash risk remains elevated compared with that for middle-aged drivers. The proportion of teenagers’ fatal crash involvements occurring at night or with multiple teenage passengers declined, consistent with the implementation of GDL laws targeting these situations, but they remain important crash factors along with speeding, driver error, and alcohol consumption.Practical application:
Although this study was not designed to examine the role of GDL, the results are consistent with the increased presence of such laws. More gains are achievable if states strengthen their laws.