Parents don't have to feel helpless when they turn over the car keys, two UNC studies suggest. Teenagers are safer behind the wheel these days, thanks to a new licensing system that involves parents in teaching teens to drive. And, teen drivers are less likely to be involved in crashes if their parents set good examples with their own driving.

The most recent of the studies shows that, since North Carolina enacted graduated driver licensing (GDL), which involves extensive supervision of beginning drivers, the number of crashes involving 16-year-old drivers has decreased dramatically. The number of fatal crashes among this group was 57 percent lower in 1999 than in 1996 (the year before GDL was enacted).

The study was conducted by UNC's Highway Safety Research Center (HSRC) and published in the Oct. 3 issue of The Journal of the American Medical Association. Investigators were Robert D. Foss, research scientist; John R. Feaganes, staff associate; and Eric A. Rodgman, senior database analyst.

GDL requires teenage drivers to safely drive during two restricted driving periods before they receive a full license. In the first stage, drivers who are at least age 15 may drive only when accompanied by a designated adult. After 12 months in this stage, and six consecutive months with no violations, drivers can move to level two, during which they may drive unsupervised between 5 a.m. and 9 p.m. They are allowed to drive after 9 p.m. only with their designated adult supervisor. After six months at this level with no violations, teenagers may receive an unrestricted license.

The study also noted other decreases in crash rates. Nighttime crashes among 16-year-olds decreased 43 percent, and daytime crashes decreased 20 percent. "These study findings strongly affirm that GDL is tremendously successful," Foss said. To control for other factors that could influence crashes, the researchers compared statistics for 16-year-old drivers with those ages 25 to 54. The authors also studied crashes per licensed driver to rule out the possibility that a decrease in the number of licensed drivers would explain any drops in crashes.

The benefits of GDL are so clear that the study authors suggest parents in states without such laws (34 states have them) follow similar guidelines for their teens--at least six months driving with an adult supervisor, then another six-month period of prohibition on unsupervised nighttime driving and driving with passengers.

Another study conducted by the Highway Safety Research Center jointly with the Insurance Institute for Highway Safety found that parents' driving practices influence their children's. From examining the records of 155,349 young North Carolina drivers, researchers found that teenagers were 22 percent more likely to have been in a crash if their parents had been involved in three or more crashes, compared with teens whose parents had no crashes on their records.

Children whose parents had three or more violations such as speeding, following too closely or reckless driving were 38 percent more likely to have a citation themselves. The UNC author of the study was Donald Reinfurt, deputy director of HSRC. It was published in the journal Accident Analysis and Prevention.

Foss and other researchers on the first study plan to examine teen driving records further to determine whether GDL has a lasting effect on teens' driving. After another year or so, researchers can compare crash rates of teenage drivers who went through GDL with those who did not. "At that point we'll have a better sense of whether we've made safer drivers or have just protected them for a year and a half or two with the various restrictions on driving conditions involved in GDL," Foss said. "If all we've done is protect them from greater risks during that time, that's still a grand benefit because we've taken the two most dangerous years of their lives and made them a lot safer."

For more information about these and other HSRC studies, visit the web site of Directions, the center's newsletter.