Nelson health services are under increased pressure due to a population rise, with the Christchurch earthquake partly to blame, but a clear picture of the change has yet to emerge.
Nelson Marlborough District Health Board general manager of corporate services Nick Lanigan said it was likely there had been a greater than normal influx of Christchurch residents to the area, but there was no accurate way of tracking the movements of people between areas in New Zealand.
There were many reasons for movements, and not everyone enrolled straight away with a PHO when they move. People had also left the district, so establishing firm numbers was difficult and could only be achieved with a census.
It was particularly hard to determine the demographics of those arriving in the area, he said.
"It seems that immediately after the quake predominately young families moved to the Nelson Marlborough DHB area.
"But in more recent times, we've had greater numbers of people over 65. Only a census will really tell us what our population make up is."
The funding model provided more funding for population groups that have higher health needs, so if the real population mix was different from the estimated mix, then funding would not match the demands placed upon health services.
There were also increased GP and community pharmacy costs, and more people presenting to the hospital for both elective and acute visits.
The year to date figures for May 2012 show Nelson was receiving about $790,000 worth of revenue for the aged residential care of former Christchurch residents.
But Residential Disability Support Services was about $1.97 million over budget, with about $1.019m of that coming from Christchurch evacuees.
This funding shortfall was a result of ex-Christchurch residents who entered residential care when they moved to Nelson, and had not already received subsidised care in Christchurch at the time of the earthquake.
Nelson Bays Primary Health organisation chief executive Andrew Swanson-Dobbs said between July 2011 and July 2012 the PHO enrolments in Nelson had jumped by 1308.
Since the typical rate for patients and GPs was 1:1300, this meant the region had required an extra GP to cover this increase.
There was no data to indicate where these people were from, he said.
"We do not know whether they have all migrated from Auckland, Istanbul, Papua New Guinea or any of them are from Christchurch."
But the increase was in line with that of previous years, although greater than that between 2010 and 2011, he said.
"There has not been an impact in general practice that is over and above the normal increase that's been experienced in the last four or five years."
Health Action Trust support manager Mary Ellis said Christchurch residents had accessed mental health services since the earthquake.
"Even quite recently we have had people who have accessed services we provide, which is understandable given the trauma that they have been through in Canterbury.
"It's good that people are accessing services in terms of their recovery."
Ernest Rutherford Retirement Village manager Durham Quigley said that since the earthquake there had been a steady stream of Christchurch retirees moving to Nelson, with some deciding to move themselves, and others asked to move by their families.
"Some of them just wanted to get out initially, with families putting pressure on them saying, `come on mum and dad it's time you move up here and be closer to us'."
Others moved after they had repaired and sold their Christchurch homes, he said.
Nelson had always been a natural place to retire, but the numbers of residents had increased due to the earthquakes, he said. Most had not been in care before coming to Nelson, and Mr Quigley said he thought retirement villages allowed them a sense of community.
"Somebody who comes up and moves into a community in town, where there's not quite the communal type living, I wouldn't know how they would be coping if they don't get out and be very active."