ACC has paid out $80 million in the past two years over claims for medical mishaps.
Last year ACC paid more than $41 million (excluding GST) in compensation to people who received "treatment injuries", a figure revealed after an Official Information Act request.
This figure, the total amount paid out from 9382 separate claims, does not include the cost of treatment or rehabilitation for the treatment injury.
Compensation payments cover loss of earnings after an injury.
According to ACC's website, treatment injuries are injuries that have a "direct causal link" to, but are not an ordinary consequence of, medical treatment by a registered health care professional.
Common types of treatment injuries include infections after surgery, pressure injuries and adverse side effects from medication.
Over the last decade compensation payments for treatment injuries have risen steadily each year - increasing by more than 600 per cent from 2006, when only $5.7 million was paid out from 2841 claims, to 2016.
However, an ACC spokeswoman said the increase in compensation payments and claims didn't necessarily directly relate to the number of treatment injuries that occurred or the quality of care patients received.
Other factors, including the demographics and health status of the resident population and the extent to which health providers and patients were able to recognise treatment injuries and lodge claims, affected the number of claims lodged during a particular year, she said.
Compensation costs sometimes accumulated from year to year when the need for compensation was ongoing, the ACC spokeswoman said.
"For example, claims decided in 2012 may have incurred payments in 2014, 2015."
Dr Andrew Simpson, chief medical officer at the Ministry of Health, said international research showed treatment injury rates at New Zealand hospitals were comparable to other countries.
He told the Herald that the Ministry was working with ACC, the Health Quality and Safety Commission, and district health boards to make treatment safer.
"There are currently [training] programmes for surgical site infection, pressure injury, and neonatal encephalopathy amongst others."
Staff in the health and disability sector were working to identify and analyse causes of treatment injuries and change processes to "drive continuous improvement", he said.
It was standard practice for medical practitioners to make patients aware of potential treatment injuries before beginning a course of treatment, Simpson said.
"Providing patients with information about the benefits and risks of all procedures is part of gaining informed consent."
Treatment injuries - The cost of ACC compensation
Treatment injuries - The number of compensation claims approved by ACC