The incidence of traumatic brain injuries in New Zealand is at "epidemic proportions", according to a scientist who found someone suffers such an incident every 15 minutes.
AAP reports the study, published in The Lancet, estimates more than 36,000 new traumatic brain injuries occur in New Zealand each year.
Professor Valery Feigin, who headed the research team at AUT University's National Institute for Stroke and Applied Neuroscience, says previous studies underestimated the extent of the traumatic brain injury problem.
"The true burden of TBI in New Zealand is far greater than expected and new strategies are urgently needed to reverse this 'silent epidemic'," Professor Feigin said.
Titled Brain Injury Outcomes New Zealand in the Community, the first such study of its kind in the world, looked at the incidence of TBI in more than 173,200 Waikato residents during 2010-11.
It found the rates of TBI, caused when an external force, such as a blow or knock to the head, disrupts normal brain function, in New Zealand were much higher that in other developed countries.
AAP reports the annual rate of 790 cases per 100,000 people was well above that of Europe (47-453 cases) and North America (51-618 cases).
It said there was difficulty in comparing studies because of variations in diagnostic criteria and methods used.
Professor Feigin said 95% of the New Zealand cases were found to be mild TBI, which was characterised by a relatively short loss of memory of the event or what happened just after the injury, and possible minor loss of consciousness.
"TBIs can and often do result in significant and long-standing deficits ranging from mild memory difficulties to dementia, seizures, depression and social disadaptation," he said, but if treated in a timely manner many of these consequences can be avoided.
"People need to know that if they've had any head injury which results in losing consciousness or being dazed and confused then they need to seek medical attention immediately."