Nearly half of girls playing high school sports have failed to report sports-related concussion injuries to coaches or trainers, a study published Thursday in the Journal of Trauma Nursing found.

Lead author Tracy McDonald of the University of Kansas Hospital in Kansas City said in many cases the student athletes don’t even realize they have concussions.

"Even when they do recognize it as a concussion, they are unlikely to report it to seek help," McDonald said in a press release.

The researchers surveyed 77 female high school athletes about head injuries and concussion symptoms. Thirty-one said they suspected they had had a concussion, and 10 of them did not tell a coach or trainer, saying it “wasn’t a big deal” and they wanted to keep playing.

Fifty-eight of the 77 said they had had symptoms consistent with a concussion but did not associate the symptoms with concussion.

Basketball players were the most likely to have had a concussion, followed by soccer players. Headache and dizziness were the most likely symptoms, followed by sensitivity to light or noise and blurred vision. Ten percent of the athletes said the symptoms lasted a week or longer.

The authors said their findings indicate the athletes just don’t understand the risks associated with concussions.

Some 3.8 million Americans suffered concussions in 2012, twice the number reported in 2002, concussion treatment company Prevacus reported. At the high school level, an estimated 300,000 concussions are suffered annually with nearly half, 47 percent, occurring among football players. About 11 percent of high school athletes have suffered previous concussions.

A study published in the Winter 2007-08 Journal of Athletic Training indicated girls are more susceptible to concussion than boys, possibly because they have weaker neck muscles.

Sports are the second leading cause of traumatic brain injuries among people 15 to 24, right behind motor vehicle crashes.