But trust in doctors is a factor as well. Even when doctors order costly treatments with serious side effects and little evidence of their being effective, as studies find is common, patients are loath to question the decision. Instead of blaming such treatments for the rising cost of medicine, many people are inclined to blame forces that health economists say are far less important, like greedy insurance companies or onerous malpractice laws.

Mr. Obama is well aware of the public perception. This is why he directs his criticism not at doctors but at insurers and drug companies. In his news conference on Wednesday night, he advocated creating a government panel with the power to begin moving Medicare away from its fee-for-service model and emphasize outcomes instead. But he described it in doctor-friendly terms  as “an independent group of doctors and medical experts who are empowered to eliminate waste and inefficiency.”

His rhetorical choices highlight one of the least discussed but most important conflicts in the current health care debate. The fight isn’t just a matter of Democrats vs. Republicans, Blue Dogs vs. liberals or patients vs. insurers. It is also doctors vs. doctors.

That’s the same as in Oklahoma in 1929. And what has happened to Dr. Shadid’s model? It has survived. He built a team of doctors who collaborated closely and were not paid based on how many procedures they performed. Today, this description fits the Mayo Clinic and the Cleveland Clinic (which Mr. Obama visited on Thursday), as well as less-known groups around the country.

Medicare data shows that these groups generally provide less expensive care and appear to deliver better results. Armed with this data, the doctors who run the groups have been lobbying Congress to make their model a bigger part of health reform. Two weeks ago, 13 such groups released a letter saying that recent versions of proposed legislation did not control costs enough.

Their goal is to weaken the fee-for-service system. In its place, doctors might receive a lump-sum payment to treat a patient with a certain condition, based on average costs elsewhere and on what scientific evidence had found to be effective. Hospitals with especially good outcomes might earn bonuses.

Advocates say such a system could ultimately give doctors more control. Rather than having to organize their schedules around the tests and procedures that insurers agree to reimburse, doctors could opt for the treatments they deem most effective. “It’s a lot more accountability, which is why it’s scary for physicians,” said Dr. Mark McClellan, a former head of Medicare under George W. Bush. “But in some ways it’s also more autonomy.”