Health insurance companies are beginning to reveal the costs of health care services, a move that might ultimately change what providers charge and how much consumers pay. Charges for services can vary by as much as 30% depending on the provider, according to Cigna. In January 2007, Cigna in 58 markets will begin to offer the Cigna Care Network, which will include doctors who score well on quality and cost-efficiency measures.

The American Medical Association in November passed a resolution seeking laws that would prohibit insurers from creating networks "based solely on economic criteria." Nancy Nielsen, head of AMA's House of Delegates, said, "You have to look very carefully at those efficiency numbers. Some are only about costs. That's where it gets tricky. That's where the biggest fights and negotiations are."

Insurers contend their efficiency measures will not be based solely on costs but add that actions need to be taken to address the cost disparities in health care. Charles Cutler, national medical director for Aetna, said, "The more people understand the cost of health care, the better off we will be." Brian Klepper of the Center for Practical Health Reform said, "We're at the leading edge of a huge change" .