Graduated driver licensing: Not a one-size-fits-all approach

Graduated driver licensing, the licensing system nearly all U.S. states have in place to help high-school-age novice drivers get driving experience and limit driving in risky conditions, has reduced crash rates among 16- and 17-years-olds. In view of the well-documented effectiveness of GDL, some advocates have begun pushing to extend GDL requirements to those who begin driving at 18 and older.

The recent article “Graduated Driver Licensing for Older Novice Drivers: Critical Analysis of the Issues,” published in the August 22, 2017, edition of the American Journal of Preventive Medicine, provides a thorough analysis of the many questions in need of research on this topic and a review of the existing evidence. The article was co-authored by HSRC researcher Rob Foss, Ph.D. (retired); Allison E. Curry, Ph. D., MPH, Center for Injury Research and Prevention, Children's Hospital of Philadelphia; and Allan F. Williams, Ph.D.

HSRC scientists developed the original concept of GDL to address specifically the risks of high-school-age drivers, and to rely heavily on parental involvement. In 1997, North Carolina and Michigan became the first states to enact full GDL systems. An optimal GDL system involves three license stages:

• a mandatory 12-month learner period requiring supervision by a licensed adult driver at all times;
• an intermediate stage of six months that allows some unsupervised driving but still requires driving supervision in high-risk conditions including while carrying multiple young passengers or driving after 9 p.m.; and
• a full driver's license.

An optimal GDL also requires a novice to keep a clean driving record (i.e., no traffic convictions or at-fault crashes) to graduate to the next stage.

Older vs. younger novice drivers

The AJPM article reviews the limited evidence on whether GDL might be beneficial for older novices. It concludes that research is urgently needed to address:

• whether older novice driver risks are as high as they are for younger teens;
• which conditions are risky for older novices (e.g., carrying passengers appears not to be as risky for this group); and
• whether older novices will comply with GDL requirements at the high rates that young novices comply (generally more than 90 percent).

Older novices have greater, more varied driving needs and may have difficulty finding a licensed adult to supervise their driving during the learner period. Both of these, as well as other issues, may make it difficult for older novices to obtain the benefits of GDL that younger novices experience. Since most questions about the promise of GDL for older beginning drivers remain unanswered by researchers, extending GDL requirements to older novices is premature.

Some research in New Jersey conducted by Drs. Curry and Williams suggests GDL may be of some benefit to 18- to 20-year-old novices. "While it’s appropriate for states to consider extending GDL restrictions to novice drivers ages 18 and up, evidence that is based on rigorous research is critical to guide the discussion," says Dr. Curry. “Recent research I conducted in New Jersey, where full GDL applies until a person’s 21st birthday, suggests that 18- to 20-year-old novice drivers experience a crash reduction benefit from their GDL nighttime driving restriction and that they comply with GDL restrictions.” Dr. Curry also explains that there is no compelling evidence to suggest extending restrictions for drivers ages 21 and older is beneficial.

Where to go from here?

There is work to be done now to improve teen driver safety, even as researchers address whether GDL is needed for older novice drivers. About three quarters of all states have adopted a learner period that is not long enough for novices to obtain the necessary supervised driving practice they need; to achieve its full potential benefit, the learner period should last 12 months.

The other major weakness of most states' GDLs is that the night driving limit for intermediate licensees—who are just beginning to drive without supervision—begins too late to address most of the teen night driving risk. Most young teen nighttime crashes occur between 9 p.m. and 11 p.m., so the limit for unsupervised night driving for 16- to 17-year-olds should be 9 p.m.

Other HSRC young driver programs

In addition to years of work on GDL, HSRC houses the Center for the Study of Young Drivers, which was established in 2005 to develop a fundamental understanding of the factors that contribute to the high crash rate among young drivers. As part of its mission, CSYD also provides guidance to communities that are interested in conducting local activities to improve teen driver safety.

In addition, the CSYD team—which includes HSRC researchers Arthur Goodwin, Stephanie Harrell, Bevan Kirley, Natalie O’Brien and Yudan Wang—is currently developing a comprehensive system to support parents of new teen drivers. Funded in part by the Collaborative Sciences Center for Road Safety, the HSRC-led University Transportation Center, this effort builds on more than 15 years of HSRC/CSYD research on the role parents play as a teen begins driving. The ultimate objective of this project is to develop, test and implement a multi-faceted, multi-step program to provide guidance to parents of new drivers in North Carolina

HSRC’s experience and that of other research groups shows that “one-shot” efforts to enlighten or motivate parents do not produce measurable improvements in teens’ subsequent crash rates. Instead, what is needed most is a comprehensive approach that provides repeated contacts with parents and targeted guidance at the time that guidance is most helpful.

Executive Editor: Caroline Mozingo
Managing Editor: Jennifer
                                Palcher-Silliman
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