More than 5300 people missed out on elective surgery over a three-month period last year, figures released by the Government show.
But the actual total of declined applications for surgery is likely to be much higher, Health Minister Jonathan Coleman said today - possibly up to 21,000 people in a quarter.
The Ministry of Health began measuring GPs' referrals to hospital specialists across all DHBs in 2014 amid concerns about "unmet need".
The first data was released this morning, showing that GPs made 145,922 referrals between July 1 and September 30. Of that total, 130,902 patients were accepted for a first specialist assessment, which is the first step towards approval for elective surgery.
Another 9685 patients had their requests delayed so further investigation could be carried out, or declined because the GP had not provided enough information or because the treatment was no longer needed.