ALBANY, N.Y. -- A new study says about a third of professional mixed martial arts matches end in knockout or technical knockout, indicating a higher incidence of brain trauma than boxing or other martial arts.

The University of Toronto study published this month in the American Journal of Sports Medicine examined records and videos from 844 bouts.

Researchers found nearly 13 per cent ended in knockouts, while 21 per cent ended in technical knockouts, usually after a combatant was hit in the head five to 10 times immediately before the fight was stopped.

The study says the MMA head trauma rate also outpaces football and hockey.

Supporters of MMA call the study flawed and say another forthcoming study will have more accurate results.

New York is the last remaining state to prohibit professional MMA bouts. Longstanding efforts to get it legalized in the state recently stalled again for advocates hoping to gain access to Madison Square Garden and other New York venues.