BOSTON, Dec. 16 (UPI) -- Seventy-six percent of U.S. high-school athletics concussions were caused by contact with another player, usually a head-to-head collision, researchers say.
The study published in The American Journal of Sports Medicine found 93.4 percent of concussions caused a headache, 4.6 percent caused loss of consciousness, 83.4 percent experienced resolution of their symptoms within a week, but 1.5 percent had symptoms that lasted longer than a month.
Study author Dr. William P. Meehan III of Children's Hospital Boston and colleagues say the study involved a total of 544 concussions recorded by the High School Reporting Information Online surveillance system during the 2008-09 school year.
Computerized neuropsychological testing was used in 25.7 percent of concussions, and in those cases, athletes were less likely than those who were not tested to return to play within one week.
Researchers found that injured football players were less likely than injured athletes participating in other sports to be examined using the computerized neuropsychological testing, the researchers say.
"Although it is now recognized as one of 'the cornerstones of concussion evaluation,' routine neuropsychological testing in the setting of sports-related concussion is a relatively new concept," the researchers say in a statement. "This is the first study, of which we are aware, to query the use of computerized neuropsychological testing in high school athletes using a large, nationally representative sample."