Waikato and Wellington public hospitals have the slowest emergency departments in the country, according to a Ministry of Health survey.
The ministry's target is for 95 per cent of patients to be admitted, discharged, or transferred from the department within six hours, but only nine of the 20 district health boards (DHBs) did so.
"The target is a measure of the efficiency of flow of acute (urgent) patients through public hospitals, and home again," the ministry says on its website.
The Waikato and Capital and Coast DHBs, the poorest performers, both moved 88 per cent of patients out of the emergency room in six hours.
Group manager of Waikato and Thames hospitals Mark Spittal described the ranking as extremely disappointing.
"We are not happy with the performance of the [Waikato] hospital . . . we have been working extremely hard on this because ultimately it is about the service that we provide to people who need care here," he said.
The top five performing emergency departments were from the West Coast, Waitemata, Whanganui, Nelson-Marlborough, and South Canterbury.
The West Coast DHB, as the top performer for this target, moved 100 per cent of patients through the emergency department in the designated time.
Waitemata, Whanganui, and Nelson-Marlborough DHBs all moved 97 per cent of patients through the department.
Auckland hit the target of 95 per cent, coming in ninth place.
Canterbury, which was the 10th-best performer, narrowly missed the target at 94 per cent.
Bay of Plenty DHB moved 92 per cent of patients out of the emergency department within six hours, in sixteenth place.
Nationally, performance increased by 1.8 per cent to 93 per cent in the last three months, the ministry said.
"Quarter-two results have been improving year-on-year with the current performance showing a 1.1 per cent increase on the result for the same period last year," the ministry said.
The ministry said long stays in emergency departments were linked to overcrowding in the department, which research showed could have negative outcomes for patients, such as more deaths and longer stays in hospital.
It could also lead to "compromised standards of privacy and dignity for patients", where patients were kept on trolleys in corridors.
Emergency Department stays were one of six indicators the ministry used to monitor DHB performance.
The health ministry looks at the performance of each DHB against the targets four times each year.
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