Health Minister Jonathan Coleman says the Government will know next year how many people are being rejected inappropriately for elective surgery.
Labour's acting health spokesman David Clark says that since 2010 almost 160,000 people have been referred back to their GPs after being unable to get an appointment to see a specialist.
Mr Clark has alleged there are "hidden waiting lists".
The Government has set a target for District Heath Boards to treat people on waiting lists for election surgery within a set time and hospital specialists have been accused of simply referring patients back to GPs so they can meet the target.
Dr Coleman says the public health system is doing 50,000 more operations a year than when National Party came into power at the 2008 general election, as well as 60,000 more surgical specialist appointments and 50,000 more general medical appointments with the specialists.
"That's what we've done," he said.
Dr Coleman said the Ministry of Health had a lot of work under way to get a picture of the unmet demand.
"There isn't any clarity around the figures, and we are the first government ever to start counting this. So later next year we'll have a true picture of the referral pathway," he told The Nation today.
He said the research would reveal what proportion of patients were referred back to GPs inappropriately and what proportion could be managed better in primary care.
In 2013, research funded by the Health Funds Association of New Zealand found 280,000 Kiwis met the clinical threshold for elective surgery, but only 110,000 had been formally placed on a waiting list.