Football players suffer about 60 percent of concussions by high school athletes, according to the Government Accountability Office, but researchers believe girls may be more susceptible to concussions than boys in some sports.
However, there is much disagreement about which sports put girls at greater risk than boys.
One study, which is used by the online concussion course of the National Federation of High School Athletic Associations, reported that girls soccer players are about twice as likely to receive concussions as boys players (35 in 100,000 to 17 in 100,000).
During congressional hearings last month, the GAO reported that girls basketball players are three times more likely to suffer a concussion than a boy playing basketball and that girls soccer players are twice as likely to receive a concussion than a boys soccer player.
But a recent study by Dr. Kevin Guskiewicz of UNC-Chapel Hill, one of the nation's leading authorities on concussions, found that boys and girls generally have the same rate of incidence of concussions in sports other than basketball and hockey.
"There were some papers that indicated that girls were much more susceptible to concussions than boys, but the most recent studies don't show that except in ice hockey and basketball," Guskiewicz said.
Cary High School had a rash of concussions in girls soccer this year with seven head injuries among six players. But an informal survey of a couple of dozen other area schools indicated most schools had one or no concussions in girls soccer this year.
Eric Hall, the certified athletic trainer at Cary High School, said he believes certified trainers, coaches and medical providers are more aware of concussions and are better able to recognize the signs and symptoms of concussions now than in the past.
"Coaches know more about concussions since the news from the NFL, NHL and other injury stories from around the U.S. are getting more attention," he said. "I bet many concussions were missed years ago."
Cary's experience this year showed the importance of carefully monitoring players with concussions. The symptoms of five of the six girls were gone within days. Those players were cleared by a doctor to return to physical activities. The sixth girl had symptoms that lasted for about a month, and she is still recovering.