Concussion grades and management recommendations*
Guideline	1	2	3
Cantu5	Athlete may return to play if asymptomatic for one week (if athlete is totally asymptomatic, return to play on same day may be considered).	Athlete may return to play if asymptomatic for one week.	Athlete may not return to play for at least one month; athlete may then return to play if asymptomatic for one week.
Colorado Medical Society6	Athlete may return to play if asymptomatic for 20 minutes.	Athlete may return to play if asymptomatic for one week.	Athlete should be transported to a hospital emergency department; athlete may return to play one month after injury if asymptomatic for two weeks.
American Academy of Neurology7	Athlete may return to play if asymptomatic for 15 minutes.	Athlete may return to play if asymptomatic for one week.	Athlete should be transported to a hospital emergency department; if athlete had brief loss of consciousness (i.e., seconds), may return to play when asymptomatic for one week; if athlete had prolonged loss of consciousness (i.e., minutes), may return to play when asymptomatic for two weeks.