This study demonstrates a perceived increase of concussion by more experienced referees ( when compared with less experienced referees ) .
It is unclear whether this is due to an actual increase or increased recognition of concussions that has been demonstrated in the literature .
This study demonstrates a perceived increase of concussion by more experienced referees ( when compared with less experienced referees ) , although it is unclear whether this is due to an actual increase or increased recognition of concussions that has been demonstrated in the literature .