A chronically-ill Rotorua woman suspects some GPs are reluctant to enrol her because she needs a lot of care, as new research shows under-funding is forcing some clinics to cherry-pick healthy patients.

Martha - not her real name - contacted a GP clinic near her new home in Rotorua before moving there, to check whether she and her elderly mother would be able to enrol.

She was told to "pop in" when she arrived in town to fill out the forms.

"But when I got down there, they said: 'Oh no, we're not taking new patients'. And I said: 'Okay, can I put our names down?' And they said: 'We'll be closed for a while'."

She contacted the local Primary Health Organisation, which managed to find her a GP - but it was much further away and more expensive.

"But I kept seeing this previous clinic advertising for new patients, although they said 'conditions apply'. So I went there and said: 'Look, I've managed to get enrolled at another surgery in town but are you enrolling patients?' And they said 'Yes, but it will have to go to a panel of something, and they will decide whether to enrol you or not'."

Martha left her name and details with the clinic that was cheaper and much closer to home and waited - only to be disappointed again.

"They said: 'Sorry, we cannot enrol you'. And I rang them and asked why, and they said: 'You don't fit the criteria'. So I asked: 'What are the criteria?'. And they basically couldn't give me an answer."

Marth is under ACC after suffering a botched surgery 20 years ago - and always books double appointments because of her complex needs.

She suspects the clinic had put her in the "too hard basket".

"How can they know just by my name whether they want to accept me?"

RNZ has approached the clinic for comment.

Half of all GP clinics pick and choose - research

Research published in The New Zealand Medical Journal last week showed about half of all GP clinics anonymously surveyed were picking and choosing which patients to enrol.

Co-author associate professor Mona Jeffreys from Victoria University says some practices were "cream skimming" the healthier patients, while others focused on those with the highest need.

Just 28 per cent of practices were fully open in 2022 - half what it was three years previously.

"So I guess what this is underlining is the real under-investment in primary care, which we know is having a real knock-on effect to hospital-level care."

Under capitation funding, GPs receive an annual "capped" payment from the government for each enrolled patient, mostly based on age, with some additional money for high health needs.

Tāmaki Health runs 51 clinics across the North Island, of which 29 are "very low-cost access practices" that get higher funding in return for keeping patient fees under $20.

Chief executive Dr Lloyd McCann says costs have risen much faster than revenue in recent years, and he could empathise with those clinics who were turning away high-needs patients.

"That's not what primary care wants to do because I really do believe that everyone working in this sector has the best interests of patients at heart.

"It's unfortunately a decision that is made for you because of the financial consequences that exist."

Based on continuing talks with Health New Zealand Te Whatu Ora, Dr McCann is confident officials understood what was at stake.

"One of our clinics in South Auckland, our Ōtara Clinic, sees 400 to 450 patients a day. If that service were to be compromised, there would be literally no other place for those patients to go, except the emergency department at Middlmore Hospital."

Health Minister Dr Shane Reti - a former GP himself - has gone on record before and after the election saying the general practice model was "broken".

He previously told RNZ the government would look at renumeration for GPs, but was yet to give a timeline for change.

In a written statement, Health New Zealand national living well director Martin Hefford acknowledged the current capitation funding system for general practice had "limitations, as it does not include important factors such as socioeconomic status or ethnicity".

"We have taken some steps to improve the way we fund general practice capability and capacity. Funding for all primary and community health services, including general practice, increased by 5 per cent from 1 July 2023. In addition, practices received more than $30 million in 2023/24 to assist with nursing pay parity."

General practices with an enrolled population of at least 50 per cent Māori and/or Pacific received an "equity adjustment" funding boost of $24.4m in 2023/24, he says.

Meanwhile, work to review the overall model of care and funding for primary care and urgent care was underway, with initial scoping expected to be completed by June.

- Ruth Hill/ RNZ