The prospective outcomes of injury study tracked a cohort of people who suffered an injury which resulted in them being placed on ACC's entitlement claims register after either being admitted to hospital, or receiving treatment without being admitted.
Lead researcher Dr Sarah Derrett, of the Injury Prevention Research Unit, said the latest analysis looked at the cohort three months after injury, and found 39.4% of the 2079 people who were not admitted to hospital had a disability.
Of those admitted, 53.6% of the 673 people had a disability.
"Often, there is an assumption that people not admitted to hospital don't have a serious injury or long-lasting disability.
"Our study has found a high proportion of those not admitted to hospital have an ongoing disability, and that's important."
Funded by the Health Research Council of New Zealand, the study aims to identify factors associated with poor outcomes and slower injury recovery.
"Internationally, we don't know enough about the outcomes of injury long term, and particularly about outcomes for those not hospitalised," Dr Derrett said.
"This study is assessing the burden of injury long term and seeing if any particular groups are at risk of a poorer outcome than others."
People with injuries traditionally seen as mild were experiencing disability, and it was important to know more about them, she said.
The findings were presented this week at the Safety 2012 World Conference in Wellington.
