Previously hidden figures about surgical procedures in South Australia show some patients have been waiting for treatment for more than 16 years at public hospitals.

The SA Government has released data about delays in the public health system, including average and maximum waiting times for non-urgent outpatients at six hospitals in Adelaide.

"Some of these waits are extremely long. It's not uncommon for a six or seven-year wait in some clinics," Health Minister Stephen Wade said.

In one case, a patient has been waiting more than 16 years for an appointment with an ear, nose and throat specialist at the Royal Adelaide Hospital (RAH).

Some patients have also been kept waiting for more than 16 years for oncology services and reconstructive surgery at the RAH.

Mr Wade described the situation as "disturbing" but admitted it would "take years" to fix.

"Figures in this table are stunning and it's very important that we have a look at some of the more serious waits, the longer waits, and see what we can do in those particular clinics," he said.

Outpatient specialty Hospital Average waiting time Maximum waiting times Plastic and reconstructive surgery Royal Adelaide Hospital Two years at least 16 years Ear, nose and throat Royal Adelaide Hospital 3.7 years at least 16 years Medical oncology Queen Elizabeth Hospital Four years at least 16 years Ophthalmology Royal Adelaide Hospital 1.6 years at least 13 years Rehabilitation Queen Elizabeth Hospital 3.4 years at least 11 years Urology Royal Adelaide Hospital 3.3 years at least 14 years

The Royal Adelaide and Queen Elizabeth hospitals had the worst maximum waiting times, while Noarlunga and the Flinders Medical Centre were better performing.

Average waiting times for rehabilitation services at the Queen Elizabeth Hospital were almost three-and-a-half years.

Mr Wade said introducing a new policy of releasing the latest elective surgery figures every three months would help inform patients about the best options for treatments.

"It will give both patients and GPs an opportunity to make informed decisions about treatment options," he said.

Mr Wade blamed the previous Labor Government for overseeing an increase in elective surgery waiting times, but Opposition Leader Peter Malinauskas defended his party's record.

He rejected a suggestion waiting times doubled under Labor, but welcomed the new transparency.

"In many areas of elective surgery waiting times there were substantial improvements as a result of the record investment that Labor made in government," he said.

"It's now incumbent on this new government to continue to see improvement in other areas as well."