Washington ? Rattled but apparently not badly hurt, Marie Helen Jadotte walked away from a car wreck, going to a hospital only at a police officer’s insistence. She was shocked to hear she had a life-threatening liver injury.

In fact, in the frantic rush after an accident, serious injuries often can go undetected without close observation by emergency crews.

Now a government-supported program linking hospitals throughout the country is seeking to document injury patterns from automobile crashes. The goals are to help doctors spot hidden injuries and aid engineers in designing safer vehicles.

“The more we understand patterns, the better we treat people,” said Dr. Jeffrey Augenstein, trauma surgeon and professor of surgery at the William Lehman Injury Research Center at the University of Miami.

The Crash Injury Research and Engineering Network, or CIREN, links 10 trauma centers by a computer network containing information on crashes, injuries and treatment, from streetside aid to hospital surgery and long-term follow-up.

In one pattern detected by the network, experts noticed that in side-impact crashes, there’s a greater potential for aorta injuries even without the chest being crushed. The shape of the chest changes and puts stress on the aorta, Augenstein said. The aorta is the main artery carrying blood from the heart.

It also was learned that with older seat-belt systems, if drivers wore only the shoulder strap, they could suffer severe liver injuries in a low-speed crash because of pressure caused by having the shoulder belt wrapped around the abdomen. If the lap belt is worn, pressure is on the pelvis and parts of the body more able to withstand the sudden stop, Augenstein said.

More recently, CIREN has taken a close look at side air bags, noting that in some vehicles the bag only protects the driver’s or passenger’s chest, leaving the head exposed. There is no federal requirement for side air bags.

Jadotte, a Miami home health nurse, credits the research with helping to save her life.

It was a sunny morning in June 1997, the day before her 40th birthday, and she was driving between patients’ homes. Her Mazda plowed into another car at an intersection.

She resisted a police officer’s recommendation that she be taken to the nearest trauma center. But the officer had noticed Jadotte was wearing only the shoulder strap part of the seat belt. He had recently learned from case studies of the risk of liver injury, and persuaded her to go to the hospital.

Doctors found she had a lacerated liver and abdominal bleeding. “I was immediately stunned,” she said.