title: How many concussions are too many?
authors: H
authors: H
authors: Kent
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001924:Brain Concussion / Q000175:diagnosis* / Q000209:etiology*; D001955:British Columbia; D006688:Hockey / Q000293:injuries*; D006801:Humans; D009483:Neuropsychological Tests; D012307:Risk Factors