Tuesday, February 22, 2005
A new program reduces the likelihood that teens will drive under conditions that place them at the greatest risk for a car crash, according to a study from the National Institute of Child Health and Human Development, one of the National Institutes of Health.
The Checkpoints Program, developed by NICHD scientists, teaches parents to limit their teenagers' exposure to certain driving conditions for the first 12 months after teens receive their licenses—the time when they are statistically most likely to get into a car crash.
The Checkpoints Program's central feature is a written agreement that parents and teens sign. The agreement limits teens' driving under conditions that place them at increased risk for a crash: driving at night, driving with other teens in the car, driving during bad weather, and driving on high speed roads. A supporting video and periodic newsletters explain the risks that new drivers face and reinforce the need for parents to limit their newly licensed teens' driving under these risky conditions.
The program is still undergoing testing and is not yet available to the general public. The study appears in the March 2005 issue of the American Journal of Public Health.
"This study shows that parents who set reasonable limits on driving can reduce their newly licensed teens' exposure to risky driving conditions," said NICHD Director Duane Alexander, M.D.
The current study builds upon an earlier study showing that families who participated in the Checkpoints Program imposed stricter driving limits on their teens, both when the teens initially got their licenses and three months later.
"The key is for parents to limit driving privileges during the months after teens get their licenses," said Bruce G. Simons-Morton, Ed.D., M.P.H, Chief of NICHD's Prevention Research Branch. "After teenagers become accustomed, for example, to driving with friends in their car, or to driving at night, it's a lot more difficult to restrict such privileges."
The Checkpoints Program, he added, teaches parents about the need to establish initial restrictions on teen driving, but also helps keep the restrictions in place for up to 12 months. Reducing the amount of time newly licensed adolescents drive in risky situations allows them to gain needed experience but while driving under safer circumstances.
Earlier studies have shown that motor vehicle crash rates for teenagers are higher than for older drivers, particularly during the first 12 months after teens get their licenses. Crash rates are highest during the first 1000 miles and 6 months of driving, regardless of the amount of supervised practice driving before a license is received and regardless of age. Currently, 35 states and the District of Columbia have graduated driver-licensing (GDL) policies, which grant driving privileges in discrete increments and temporarily restrict high-risk driving conditions. GDL has been shown to reduce crashes among teen drivers, but GDL policies vary from state to state. One effect of GDL is to empower parents to restrict the driving of their newly licensed teens.
The Checkpoints Program was designed to help parents set limits on the conditions their teens drive under. To conduct the study, Dr. Simons-Morton and his colleagues recruited pairs of parents and teens at 8 offices of the Connecticut Division of Motor Vehicles. In all, 420 parent-teen pairs participated in the study and were asked to complete questionnaires on their knowledge of teen driving habits. The parent-teen pairs were then assigned at random to receive either the Checkpoints materials (210) or to receive a set of materials about driver safety issues such as airbags and seatbelts (210).
Over the following year, families receiving the Checkpoints Program materials were mailed a video that covers the risks of teen driving, a series of eight newsletters during the learner's permit period and 10 additional newsletters during the first six months after getting their licenses, as well as a parent-teen driving agreement.
The agreement encourages parents to strictly limit adolescent driving under high-risk conditions and gradually increase driving privileges as teenagers gain experience and show responsible driving behavior. The agreement also helps parents establish clear driving rules, establish consequences for rule violations, and identify markers of experience and success.
The comparison families received an agreement on driving safety and were mailed general information about driver safety. Both groups received the same number of newsletters of similar design and quality at approximately the same time.
The researchers interviewed the parent-teen pairs by telephone to assess their views on teens driving. The first interview took place when the teens received their learner's permits, and assessed their likelihood of driving under risky conditions with a set of 12 items. Three months after the teens received their licenses, parents and teens were again interviewed about 4 items on teens' driving. At 6 months, the teens were interviewed again on the same 4 items, and, at 12 months, both parents and teens were interviewed about these items a final time. As expected, the group receiving the Checkpoints materials reported greater limits on teen driving conditions than did the comparison group.
The researchers already knew from their earlier study that families using the Checkpoints materials reported increased driving restrictions, both at the time teens received their licenses and three months later.
The current study, however, found that these limits carried through 6 and 12 months after the teens received their licenses.
Of the Checkpoints group, 44 percent of parents and 48 percent of teens reported adopting the agreement. Of the group who adopted the agreement, 84 percent of parents and 72 percent of teens said they were still using the agreement after 3 months. By 12 months, 73 percent of parents and 54 percent of adolescents said they were still using the agreement. In contrast, the comparison group parents were less likely to set such limits. Similarly, the limits that were put in place for the comparison group teens did not last as long as the limits established for the Checkpoints teens.
Mothers maintained greater and longer-lasting limits than did fathers, and limits were greater and longer lasting for teenagers who were younger when they received their licenses.
Dr. Simons-Morton explained that while the study showed the Checkpoints Program reduced teens' exposure to risky driving conditions, it was not large enough to determine whether the program could reduce the number of crashes. He added that he and his colleagues are currently conducting a larger, statewide study of 4000 Connecticut teens to determine if Checkpoints can reduce the crash total.
Since it's still in the testing phase, the Checkpoints Program is not available to the public. Dr. Simons-Morton added, however, that parents could limit newly licensed teens from driving under the conditions that place them at greatest risk:
The NICHD is part of the National Institutes of Health (NIH), the biomedical research arm of the federal government. NIH is an agency of the U.S. Department of Health and Human Services. The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation.