Sports-related concussions are costing ACC more than $1 million a year, with league playing Maori disproportionately costly, a study has found.
Some 20,902 concussion claims were made in the decade from 2001, across seven sporting codes, the study found.
The total cost to ACC was $16,546,026, said the study, published in the Journal of Science and Medicine in Sport.
Moderate to serious concussions accounted for just 6.4 per cent of claims (1330) but 79.1 per cent of the total cost ($13,039,416).
A moderate to serious concussion involved a combination of medical care, rehabilitation costs and income replacement for employment time lost as a result of the injury.
Of concern was the damage done to league players.
They made significantly fewer moderate to serious claims than rugby union players (179 to 802), but cost on average $25,545 per concussion, when the figure for rugby was $7797.
It suggested head injuries sustained in rugby league were more severe and took longer to recover from.
Maori league players were particularly affected, with a mean cost of $43,604 per concussion, almost double any other ethnicity per sport.
"This may be reflective of the nature of rugby league when compared with rugby union or the management of these types of injuries," the study said.
It pointed to other studies which found rugby league had a higher rate of tackles involving contact to the head than rugby union (89.9 per 1000 tackles compared to 0.6 per 1000 in rugby union).
Despite that, rugby union had four times more reported moderate to serious concussions than rugby league but the study suggested there was an issue with league under-reporting concussions.
"The overall knowledge level of concussion identification and management was only 42 per cent for rugby league team coaches and trainers in New Zealand," the study said.
Age was also a determining factor in cost, as the 30-39-year-old age group registered the highest mean cost ($19,910 per concussion).
The study suggests this is because earnings-related compensation claims are greater in this age group compared with lower earning, younger players.
The worst concussions come from when people continue to play after being concussed, so the study suggests a wider understanding of concussion identification is required to remove players from play at the first sign of concussion.
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