Does the Maryland graduated driver licensing law affect both 16-year-old drivers and those who share the road with them? Bevan B. Kirley a, ⁎ , Andrea Feller a , Elisa Braver a,b,c , Patricia Langenberg a a Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, 660 W. Redwood Street, Baltimore, MD 21201 b National Study Center for Trauma & EMS, University of Maryland School of Medicine, 701 W. Pratt St, Rm. 526, Baltimore, MD 21201 c War-Related Illness and Injury Center, Washington DC VA Medical Center, 50 Irving St. NW, Washington, DC 20422 Received 30 May 2006; received in revised form 11 May 2007; accepted 13 December 2007 Available online 25 April 2008 Abstract Problem: To assess effects of the 1999 Maryland graduated driver licensing (GDL) law on both 16-year-old drivers and other road users. Method: Calculation and comparison of crash involvement rates and non-fatal injury rates pre-GDL (1996–1998) and post-GDL (2001–2003) by type of road user, per population, and per licensed driver, with adjustment for trends among 30–59-year-old drivers. Results: Post-GDL, prevalence of licensure decreased 24% among 16-year-olds, and rates of 16-year-old drivers involved in crashes significantly decreased per 16-year-old population (corrected rate ratio (RRc) 0.82; 95% CI (0.71, 0.96)). A significant decrease also was observed for non-fatal injuries per 16-year-old population among 16-year-old drivers involved in crashes (RRc 0.63; 95% CI (0.41, 0.98)). Similarly, decreases, albeit not statistically significant, were observed among their passengers and other vehicle occupants. Per 16-year-old licensed driver, a slight non-significant increase was observed in crash involvement rates; non-fatal injury rates per 16-year-old licensed driver suggest decreased risk (non-significant) among 16-year-old drivers, their passengers, and other vehicle occupants. Summary: Maryland's GDL delayed licensure and reduced crashes and non- fatal injuries among 16-year-old drivers per population. Trends in injuries among other road users involved in crashes with 16-year-old drivers were suggestive of a benefit from GDL, although observed decreases were not significant. Per licensed driver, findings were not significant, but suggested little change in crash involvement and decreased non-fatal injuries. Because one-third fewer 16-year-olds were licensed post-GDL, these results may suggest a selection effect in licensure. Impact on Industry: Because Maryland had nighttime restrictions for new drivers before 1999, this study suggests other components of GDL are beneficial for drivers and possibly for other road users. States with weak GDL laws should strongly consider revising them. © 2008 National Safety Council and Elsevier Ltd. All rights reserved. Keywords: Graduated Driver Licensing; Teenage Drivers; Traffic Safety; Injury Prevention 1. Problem A large body of research has shown teenagers to be the highest risk age group for involvement in motor-vehicle crashes (Ulmer, Preusser, Williams, Ferguson, & Farmer, 2000). These high crash rates are generally attributed to driver immaturity and inexperience (Williams & Ferguson, 2002; McKnight & Peck, 2002; Cvijanovich, Cook, Mann, & Dean; 2001). Graduated Driver Licensing (GDL) is designed to reduce the risks of teenage drivers by phasing in driving privileges, starting with supervision and lower risk driving circumstances and then progressing to full privileges (Insurance Institute for Highway Safety [IIHS], 2004; Williams & Ferguson, 2002; Shope & Molnar, 2004; Ulmer et al., 2000; Shope, Molnar, Elliot, & Waller, 2001; Dee, Grabowski, & Morrisey, 2005). A Cochrane review of GDL research in 2004 concluded that GDL programs are generally beneficial (Hartling et al., 2004). Reduced teenage crash involvements following GDL have been reported in numerous states and provinces, including California, Michigan, Florida, Kentucky, North Carolina, Ohio, Utah, Journal of Safety Research 39 (2008) 295 – 301 www.nsc.org ⁎ Corresponding author. Tel.: +1 703 247 1609; fax: +1 703 247 1587. E-mail address: bevankirley@gmail.com (B.B. Kirley). www.elsevier.com/locate/jsr 0022-4375/$ - see front matter © 2008 National Safety Council and Elsevier Ltd. All rights reserved. doi:10.1016/j.jsr.2007.12.005