Crashes and near crashes are more common in the first six months of independent driving than in the following year, a new study that observed teenage drivers using cameras and other sensors has found. Previous research has shown that teen crash rates decline quickly as young drivers gain experience (see "Young drivers' crash rates decline sharply under graduated licensing in 3 states," Feb. 17, 2001), but the study by the National Institutes of Health and the Virginia Tech Transportation Institute is the first to use in-vehicle monitoring to confirm that trend.
In the study, vehicles driven by 42 newly licensed 16 year-olds were equipped with cameras, sensors, and computers. For each trip, the devices collected information on passengers, crashes, and near crashes. Data also were gathered when parents drove the vehicles.
A total of 40 crashes and 279 near crashes by all drivers were recorded during the 18-month study period. Teens' rates of both crashes and near crashes per distance driven were higher during the first 6 months than the prior year. The teenagers had 13.3 crashes or near crashes per 16,000 kilometers in the first period and 8.5 in the second. As expected, the teen crash and near crash rates were much higher than those of their parents. The teen rate averaged about 10 per 16,000 kilometers during the entire 18 months, while the parent rate was about 2.
In a separate analysis of data from the same study, researchers looked at different variables such as the presence of adult or teen passengers to see how they affected the young drivers' crash and near crash rates. In addition to crashes and near crashes, the researchers also measured risky driving, including things like rapid acceleration, hard braking, and hard turns.
Not surprisingly, teens drove better when they were with their parents. In the presence of adults, the rate of crashes and near crashes was 75 percent lower, and risky driving fell 67 percent compared with teens driving alone. When other teenagers were in the car, the crash/near crash rate did not vary, and risky driving was 18 percent less frequent than when the teenagers drove alone. Those results were surprising because fatal crashes are known to be more likely when there are teenage passengers riding along.
The researchers also looked at how rates of risky driving among teens changed over time. They found these rates were nearly 5 times as high as those of their parents and didn't decline as the teenagers gained more experience at the wheel.