February 6, 2007
Personal Health
New York Times

For Teenagers, the Car Is the Danger Zone

By JANE E. BRODY

Parents of teenagers worry about lots of things: drugs, sex, poor choices of friends. But the activity that causes the most harm to older teenagers is none of the above.

Motor vehicle crashes are the leading cause of death for 16- to 20-year-olds, with about 5,500 teenage drivers or passengers dying each year. In addition, about 450,000 teenagers are injured, 27,000 of them requiring hospitalization, the American Academy of Pediatrics reported in the December issue of its journal, Pediatrics.

Of those who are killed, 63 percent are drivers and 37 percent are passengers, with boys accounting for two-thirds of the fatalities. Although teenagers represent only 6 percent of drivers, they are involved in 14 percent of fatal crashes. And the crash rate among the youngest drivers — 35 crashes per million miles driven by 16-year-olds — is nearly nine times the rate of the general population.

To reduce the risks, the academy recommends that parents have teenagers sign a “driving contract” that covers when the teenager can use the car and who can be in it. It should have a provision, the academy says, that driving privileges will be revoked if the contract is violated.

Experience Matters

Although factors like alcohol, drugs and distractions like the stereo naturally come to mind, the single biggest reason for both fatal and nonfatal crashes involving teenage drivers is inexperience. In one study, the highest crash rate occurred during the first month after teenagers got their license. That rate, 120 crashes per 10,000 drivers, dropped to 70 crashes within five months.

Traditional driver education programs, which offer 30 hours of classroom instruction but only 6 hours of on-the-road training, “are not effective in creating safe drivers and decreasing crash risk,” according to the academy’s review of research. “In fact, some studies show that high school driver education programs encourage early licensure of the youngest, most dangerous drivers, with resulting increased crashes, injuries and deaths.”

Of course, alcohol, marijuana and other drugs, including prescribed and over-the-counter medications, are prominent factors in crashes involving teenagers. Though teenagers drink and drive less often than adults, they are more likely to crash when they do drink, especially at low and moderate blood-alcohol levels.

Studies have shown that marijuana impairs driving performance, especially when it is combined with alcohol. Legal drugs like antihistamines and sedatives also interfere with driving skills — again, especially when combined with alcohol. A 50-milligram dose of the antihistamine Benadryl has a greater effect on driving performance than a blood-alcohol level of 0.01 percent, one study has shown.

One drug that helps to improve driving skills is the stimulant methylphenidate, known by the brand name Ritalin, when taken by teenagers with attention-deficit hyperactivity disorder. The drug decreases the risk of errors caused by inattention.

Distractions inside the vehicle contribute to accidents for both teenage and adult drivers. But distractions are a more serious problem for novice drivers because they tend to look away from the road for longer periods and may then drift out of their lane or fail to respond in time to a hazard.

The academy noted that “eating, drinking and adjusting the radio or the climate controls each cause more crashes than cellular phone use.” Hands-free cellphones have not reduced the risk significantly, the academy said.

Teenagers also tend to be greater risk-takers. They are much less likely than adults to use safety belts, especially when driving with other teenagers. And their use of belts is least likely in the most dangerous of conditions: when driving at night, under the influence of alcohol or with several teenage passengers. In crashes that occurred in 2004, 58 percent of the teenage occupants who were killed were not wearing a seat belt.

Safer Driving

Nearly all states have so-called graduated licensing laws, some of which significantly increase the number of supervised hours of driving by teenagers while they are learning. These laws force a new driver to pass three stages: a learner’s permit, an intermediate or provisional stage and finally a regular driver’s license. For each stage, there are restrictions and minimum time requirements, and proficiency in driving skills must be demonstrated before the teenager can graduate to the next stage.

For example, during the intermediate stage, a driver may not be allowed to have more than one teenage passenger or to drive at night without adult supervision.

The Insurance Institute for Highway Safety says that in the 23 states (as well as the District of Columbia) with the best licensing laws, fatal crashes involving drivers ages 15 to 17 declined by 19 percent since those laws started taking effect in the mid-1990s. States with weaker laws experienced no benefit, the institute says. Even in states that have not adopted all the elements of graduated licensing, restrictions involving night driving and the number of teenage passengers have been found to improve driving safety.

While many states exempt school, work and religious activities from nighttime driving restrictions (the idea is to limit high-risk recreational driving at night), those states with restrictions that start before midnight have experienced a 13 percent decline in evening crash fatalities among drivers ages 15 to 17. As many as 58 percent of fatal nighttime crashes by teenage drivers occur in the three hours before midnight.

But laws are only as good as their enforcement, which is often lax. Thus, parents are likely to have the greatest say in how safe their teenage drivers are. One consideration is the vehicle itself. Rather than giving teenagers a small, old car that is less crashworthy and lacks modern safety features, or an S.U.V. that can overturn easily, or a sports car that encourages fast driving, parents should think of safety first in selecting their teenager’s vehicle.

In the driver contract the academy suggests, teenagers must promise to obey all traffic laws and speed limits; drive only when free of alcohol and drugs and never allow these substances in the car; always wear a seat belt and insist that their passengers do too; never eat, drink or use a cellphone while driving; drive only when alert and emotionally controlled; and drive with both hands on the wheel.

Parents can add restrictions on night driving, the number of teenage passengers, driving in bad weather and adjusting the stereo while driving. Teenagers should also promise to call a parent for a ride if they are impaired in any way that can impede safe driving.

The contract should also include specific penalties for violations: “No driving for ___ weeks/months” if the teenager violated the restrictions on night driving or number of passengers, failed to use safety belts or got a ticket for speeding or some other moving violation.

The academy recommends strict restrictions for the first six months, including a ban on teenage passengers and no driving after 9 p.m., for example, then gradual relaxation of restrictions if the teenager continues to demonstrate the ability to drive without committing a moving violation or getting into an accident.