A new report has revealed more than 500 patients suffered from medical failures in the 12 months to June - including a delayed caesarean delivery, which contributed to a baby's death.
A total of 520 adverse events were reported to the Health Quality and Safety Commission by district health boards (DHBs) and 154 by other providers between July 1, 2015 and June 30, 2016.
The commission today released its annual report citing a notable increase in ophthalmology events, and in some cases eye conditions deteriorated.
It shows a drop in hospital falls, but an increase in delays in diagnosis and treatment.
Adverse events in this year's report include:
Clinical management events were the most frequently reported by DHBs, with 245 incidents, making up almost half of the reported adverse events. They include those relating to delays in treatment, assessment, diagnosis, observation and monitoring (including patient deterioration). Ophthalmology events fall into this category.
Breakdown of the types of events (Health Quality and Safety Commission)
This year, 44 events relating to ophthalmology were reported, largely by the Southern and Nelson Marlborough DHBs.
"This is a prompt for other DHBs to look closely at their ophthalmology services to ensure people are being seen in a timely manner, with high-risk patients prioritised," says commission chair Professor Alan Merry.
"We anticipate more of these events will be reported next year, as DHBs focus on improving reporting in this area."
Serious harm from falls were the second-most common adverse event, with 237 incidents. Of these, 84 resulted in the patient suffering a broken hip. That's a 14 percent decreased in falls from the 277 recorded last year, although the number of broken hips remained the same.
There were 21 cases of medication mistakes.
A total of 154 adverse events were reported to the commission by providers other than DHBs. That's up from 67 last year. The majority - 101 - of those were reported by ambulance services, compared to nine the previous year.
The significant increase is being put down to a push to identify and learn from adverse events. In the last year, the ambulance sector has established an adverse event review group.
The New Zealand Private Surgical Hospitals Association reported 48 incidents.
"While it is too late to prevent these particular events, we owe it to those affected to take a thorough look at what went wrong, so we can continue to improve systems and make care safer," says Prof Merry.