• An estimated 3.8 million concussions occur each year as a result of sport and physical activity.
• Sport-related concussions account for 58 percent of all emergency department visits in children (8-13 years old) and 46 percent of all concussions in adolescents (14-19 years old). 
• Athletes who have had one concussion are 1.5 times more likely to have a second; those who have sustained two concussions have a nearly three times greater risk and those with three or more have a 3.5 times higher risk. 
• The most recent data from the High School Reporting Information Online (RIO) indicated that concussions in interscholastic athletes are responsible for 8.9 percent of all athletic injuries.

More research needed 

The clinical practice recommendations set forth in the NATA's statement are "graded" based on the Strength of Recommendation Taxonomy (SOR)(e.g. "A" is based on "consistent and good quality experimental evidence; "B" on inconsistent or limited quality experimental evidcence, and "C" on consensus, usual practice, opinion, or case series or studies of diagnosis, treatment, prevention, or screening, or extraopolations from quasi-experimental research.  

As McLeod notes, "the grading of the SOR still finds a lot of recommendations graded with a "C", meaning there is limited evidence and it is based primarily off expert opinion. (In fact, 30 of the 46 recommendations are graded C)  I think the number of C recommendations shows there is still a lot of research that needs to be done in many areas." 

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