Some policy experts said that price information alone will not tame America's health care costs because consumers are not the ones making the expensive decisions.

Mark W. Legnini, a consultant who runs the Healthcare Decisions Group in Washington, said buying a hospital stay was not like buying shoes. "You don't know what you're going to buy," he said. "The doctor determines what you're going to buy."

Karen Davis, president of the Commonwealth Fund, which works on improving health care, wants more public information about variations in hospital prices and quality. But not for the reasons most people think. "I don't think giving patients price information, even quality information, is going to drive the markets very much in terms of patients changing behavior," she said. "I think it's really important to do these things because it will change the hospitals'
behavior."

Hospital prices are difficult to compare because:

• Insured patients are paying different prices, based on what their insurance companies have negotiated with the hospital.
• Deductibles and copayments vary widely.
• Doctors often send separate bills.
• For complex problems, different patients receive different treatment.
• “Charges,” the prices most commonly released by hospitals, are like the list price for a car. Almost no one actually pays that much.
• People without insurance can receive free care or significant discounts based on their income, but the amounts vary by hospital.