( Health.com ) -- State laws that place restrictions on teenage drivers and require them to `` graduate '' from an intermediate license to a full license do seem to prevent fatal crashes involving teens , but only among the youngest drivers . A new analysis of national crash data published this week in the Journal of the American Medical Association found that between 1986 and 2007 , the rate of fatal accidents involving 16-year-old drivers was 26 % lower in states that prohibited teens from driving at night and carrying certain passengers , compared to states with neither restriction . Among 18-year-olds , however , strong graduated driver licensing ( GDL ) programs were associated with a 12 % increase in the fatal crash rate , which effectively cancelled out the benefits among younger drivers . When teen drivers of all ages were pooled together , the link between these programs and the rate of fatal crashes was statistically negligible . Health.com : Your car made healthy . `` Right now , we 're not getting the net effect across all teens that we 're hoping for , '' says Scott V. Masten , Ph.D. , the lead author of the study and a researcher at the California Department of Motor Vehicles , in Sacramento . `` We 're getting this washout where we do save some lives overall , but not nearly what we thought it [ would be ] . '' Since the first GDL programs were established in 1996 , there have been 1,348 fewer fatal crashes involving 16-year-old drivers and 1,086 more involving 18-year-olds , according to the study . Masten and his colleagues ca n't explain the increase in traffic deaths among 18-year-olds , but they suggest that it may be a form of `` payback '' for the restrictions on younger drivers . By limiting teen driving , they explain , graduated-license laws may deprive younger teens of valuable driving experience , and in some cases may lead teens to delay getting a license altogether . `` They 're saying , 'Forget it . I 'll wait till I 'm 18 , ' '' Masten says . `` We have , at least in California , more novice 18- and 19-year-olds with no driving experience . '' Health.com : 7 ways to drive like a pro . GDL programs are now in place in one form or another in all 50 states plus the District of Columbia . Every state requires would-be teen drivers to first get a learner 's permit , during which they can drive only with a parent or other adult , but beyond that the strength of the programs varies . For the purposes of the study , Masten and his colleagues considered GDL programs that prohibit teens from driving after 1 a.m. and carrying certain passengers to be `` stronger , '' while they considered programs with just one of those restrictions to be `` weaker . '' The pattern of fatal crashes associated with weaker GDL programs was similar , though less pronounced , than the pattern seen with stronger programs . In states with weaker programs , fatal crash rates were 16 % lower among 16-year-olds and 10 % higher among 18-year-olds than in states with neither of the two key restrictions . Health.com : Your emergency car kit . `` The expectation was that older [ teen ] drivers would n't be affected much one way or the other , so this is a new thing to think about , '' says Anne McCartt , Ph.D. , senior vice president for research at the Insurance Institute for Highway Safety , an Arlington , Va.-based nonprofit organization dedicated to reducing traffic deaths and accidents . But McCartt , who coauthored an editorial accompanying the new study , says this and other research suggests that GDL programs do help protect younger teen drivers . Although `` the evidence is mixed at this point about how GDL affects older teens , '' she says , `` I do n't think there 's any study that has n't found a large benefit for 16-year-olds . '' Health.com : How to be safe -- not sorry -- behind the wheel . The study had some important limitations that will need to be addressed in future research . For one , the authors looked only at fatal accidents , which account for a small percentage of all crashes and are n't representative of accidents as a whole . ( Alcohol and speeding are more often a factor in fatal crashes , for example . ) Masten and his colleagues also suggest that the findings from their nationwide analysis do n't necessarily reflect the effectiveness of specific GDL programs , given the variety in state laws . The age restrictions surrounding graduated licenses differ between states , Masten notes , as do the laws concerning learner 's permits , passengers , and nighttime driving . Copyright Health Magazine 2011 .
Rate of fatal accidents involving 16-year-old drivers was 26 % lower in states with restrictions . Strong graduated driver licensing ( GDL ) programs associated with a 12 % increase in fatal crash rate . Comment: