Higher Physician Fees Drive Up U.S. Health Costs : The higher fees paid by insurance companies for hip replacement seem to be major contributors.

In Canada, France, and Germany, the pay gap was smaller: primary care physicians earned 60% of their surgery colleagues.

The pay gap between primary care and hip replacement surgery “is where the blinking red light is, that something is out of whack in the U.S.,” Mr. White said.

The research also shows that “it's not at all the case that primary care is underpaid, but more that the surgeons and specialists are overpaid,” he said.