While young drivers are generally as cautious as their parents when driving under a learner's permit, their risk of a crash increases after they start to drive on their own.

The National Institutes of Health recently conducted a study analyzing the behavior of teen drivers, starting with the beginning of their learning period and extending through the end of their first year of independent driving. A total of 90 Virginia teenagers, as well as 131 of their parents, were observed using software and cameras installed in their vehicles.

The study concluded that teenagers were eight times more likely to be involved in a crash or near-miss in the first three months after getting their driver's license than in their last three months with a learner's permit. Teens were also four times as likely to engage in risky behaviors—including sudden acceleration, hard braking, or aggressive turning—in the first three months of driving on their own.

"Given the abrupt increase in driving risks when teenagers start to drive independently, our findings suggest that they may benefit from a more gradual decrease in adult supervision during the first few months of driving along," said Bruce Simons-Morton, a study author and senior investigator at NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development.

Overall, risky driving behaviors declined only modestly during the first year of independent driving while the rate of crashes and near misses among teenagers held steady. Researchers said this finding suggests that teen drivers are slow to learn from their early solo experiences on the road, since driving risks would otherwise decline steadily throughout the first year.

The risky driving rate among male and female drivers did not differ significantly during the learning period. Once they entered the independent driving stage, however, males were more likely to exhibit risky driving behaviors. The rate of risky driving behaviors among females dropped faster during the first year of independent driving than the male rate. The rate of crashes and near misses was similar across genders.

Some factors influenced how likely a young driver was to take risks. Teens were more likely to exhibit risky driving behaviors during the day and on dry roads and less likely to take risks in unfavorable conditions, such as during the night and on wet roads.

The study was intended to identify what factors can improve safety and reduce driving risks among young drivers. NIH also plans to look into how the duration and quality of practice driving influences a driver's behavior once they start to drive independently, and how the presence of passengers affects driving risk during both the learning and independent driving periods.

"During the learner's permit period, parents are present, so there are some skills that teenagers cannot learn until they are on their own," said Pnina Gershon, the study's lead author. "We need a better understanding of how to help teenagers learn safe driving skills when parents or other adults are not present."

Several states have graduated driver licensing programs, which include a number of requirements for teen drivers in an effort to get them more accustomed with driving. In Connecticut, a teen driver with a learner's permit needs to have at least 30 hours of classroom training and 40 hours of on-the-road instruction before they can qualify for a driver's license.

In addition, drivers under the age of 18 are subject to a number of limitations. These include restrictions on passengers for the first year of independent driving, a curfew until their 18th birthday, a requirement to use seat belts, and a prohibition on cell phone use and other mobile electronic devices.