The study comparing injuries among high school football players to those among college players is the first of its kind, to the best of anyone's knowledge. Not that information on high school athletes is easy to come by, because it's not.

The research team at the Center for Injury Research and Policy at Columbus Children's Hospital and Ohio State University used an Internet-based system to record high school athletic injuries, a system which it established only a couple of years ago, and then compare those results with data from the National Collegiate Athletic Association. Her team purposely made the high school system identical precisely to facilitate those comparison, said R. Dawn Comstock, lead researcher and an assistant professor at the university's medical college.

During the last decade, her group wrote recently in the American Journal of Sports Medicine, participation in high school football has increased by 12.2 percent with more than 1 million teen males taking part in the sport. It also has the highest injury rate of any high school sport. A previous project Comstock worked on, and which was published last year, found that for every 1,000 instances when a player was either in a practice or a game, there were 4.3 injuries.

A detailed prior study done in the late 1990s found a rate of 8.1 injuries for every 1,000 times in practice or a game, still twice the rate of the next most-injurious sport, which was basketball.

Some items of interest from Comstock's group:

* The most common sites injured were knees and ankles.

* Running plays were the most common source of injury in both high school and college, but they were a greater proportion of injury in high school competitions.

* In high school, 9.5 percent of injuries ended players' careers or seasons, but in college it was 7.3 percent. A caveat is that college seasons are longer so players have a greater chance of recovering and playing again.

* More college injuries occurred during practice, but more high school injuries occurred during competition.

Information came from a group of about 100 high schools selected to represent every part of the country. And compiling injury data depended on the cooperation of certified athletic trainers, people who have gone through many hours of education and qualification, who are associated with the National Athletic Trainers Association, and who thus have the ability to accurately report on players' injuries.

The problem is that many of these positions across the nation are being limited or eliminated because of school budget problems, Comstock's team wrote. So her group asked for only the basic information because of the burden of work placed on these people by the need to check equipment, attend to injuries, and so forth, because even though the online form required only five minutes per injury, that time adds up quickly when there are many injuries every week. They asked for only the primary injury. The NCAA, by contrast, reports every injury.

"We're fairly confident that we're only capturing the tip of the iceberg," Comstock said.

"We definitely do not want any of our research to scare parents into pulling their kids out of sports, or preventing their kids from being involved in sports. We know that we have an epidemic of obesity in our country, and the best tool that we have to fight obesity is physical activity. The main way that kids in the United States incorporate physical activity into a healthy lifestyle right now is sports

"Our aim is to make sports as safe as possible for kids to play so that more kids will be encouraged to get up off the couch and join in on the fun."