In fact, as the number of specialists has grown, the proportion who stick to the Medicare fee schedule has drastically decreased, according to Grattan Institute researcher Stephen Duckett.

Dr Duckett presented his findings to a summit in Sydney on Friday, when he described ''a whole swag of carrots at the moment, and no stick" in dealing with a critical shortage of intern places for junior doctors.

He said forcing the junior doctors to charge lower fees as specialists, work in rural or regional areas, or undertake training in medical specialties that have shortages would provide a ''stick'' that could address the shortage of intern places and cap increasing fees.

He argued the intern training year, which doctors must complete to become qualified, was extremely valuable, and authorities should consider getting interns to contribute more for the privilege.

"We know that the existing incentives to get people to work in rural and regional areas and to get people to work in the right specialties aren't working," he said.

Surgeons, anaesthetists and internal medicine specialists are the three occupational groups with the highest mean taxable income in Australia, he said. Yet workforce shortages and high fees still plagued the industry.

"People would be forced to make a choice in line with where our needs are," he said.

But the AMA president, Steve Hambleton, said he believed interns were valuable and should not face additional conditions on their training.

"While this is their final year of their training, they are actually working, they are providing services in the hospital," he said. "If you didn't have them you would have someone else on a higher pay scale.''

The crisis in intern places occurred because universities increased medical degree places to deal with doctor shortages. But jobs for interns, which combine work and further training, have not kept pace.

Dr Hambleton said there was no need for "sticks" to force doctors to work in rural and regional areas, but more needed to be done to deal with issues such as shortages of jobs for their partners.

The president of the Australian Medical Students' Association, Ben Veness, said Dr Duckett's analysis did not make sense, because if doctors charged according to demand they would keep raising their prices until people stopped trying to access their services.

"In a supply and demand driven model we wouldn't have waiting lists," he said.