Research funded by the National Institutes of Health indicates graduated licensing programs, which grant driving privileges to new drivers in phases, significantly reduce the rate of fatal crashes involving teen drivers.

All 50 states and the nation's capital adopted a graduated licensing program of some sort from 1996 to 2011, with an estimated reduction of between 8 and 14 percent in the rate of fatal crashes among 16- and 17-year-olds.

Researchers found several key characteristics of successful programs, including minimum ages of 16 to secure a learner's permit, 17 for a provisional license and 18 for a full license. Other factors were requiring at least six months between getting a permit and a provisional license, limiting nighttime driving and driving with teen passengers and requiring at least 50 hours of supervised driving.

"These studies not only confirm the effectiveness of graduated licensing approach, they also identify additional protective factors," said National Institute of Child Health and Human Development (NICHD) chief of Demographic and Behavioral Sciences Rebecca Clark.

The effect was most pronounced in states which adopted other laws, such as legislation mandating seatbelt use, requiring drivers' licenses be revoked in the event of underage possession of alcohol or limiting driving at night. As accidents and damages are reduced, lower auto insurance rates may be an added benefit, along with safer roads.