A new study suggests teens are better off staying out of the front seat of airbag-equipped cars until they're almost old enough to get behind the wheel.

While current federally mandated warning labels in cars flag a risk for airbag injuries for children 12 and under, researchers at Oregon Health Sciences University found that the injury risk from passenger air bags remains high through age 14.

"Eight years ago, when the National Highway Traffic Safety Administration issued its recommendations, they were based on the best information (about air-bag safety) available at the time," said the author of the new study, Dr. Craig Newgard, an assistant professor of emergency medicine at the university's Center for Policy and Research in Emergency Medicine.

"Those warnings worked in reducing injuries to children, but as a parent and emergency physician, I felt it was time to study whether more children could be at risk and assess whether age or body size were good measurement guidelines," he added.

Motor-vehicle crashes overall remain the leading cause of death for Americans aged 3 to 33, but research on restraint systems and safety for older children has been limited.

In research published Monday in the journal Pediatrics, Newgard looked at what happened to 3,790 children aged 1 month to 18 years who were seated in the right front seat of a vehicle and involved in a crash.

The information came from a nationally representative database of police reports on crashes over an eight-year period maintained by the National Highway Traffic Safety Administration. The agency reports that more than 150 children through age 11 have died from air-bag injuries as of mid-2004, but information on teens has been sparse.

The study found that children 14 and younger were at high risk for serious injury from air bags when they sat in the front passenger seat during car crashes.

In contrast, air bags had a protective effect for teens aged 15-18. And the study showed that age may be a better indicator of risk from air-bag injury than height or weight.

Newgard and co-author Dr. Roger Lewis, an emergency-medicine researcher at the University of California-Los Angeles, said several body changes that take place during puberty, including muscle mass, bone density and bone-mineral content, may help explain why body size alone isn't a good measurement of risk from the air bags in children.

"Anyone who drives needs to be empowered with this information," said Newgard. "When my 13-year-old nephew wants to sit in the front seat now, I won't let him."