As of last month, a federal rule called the Hospital Price Transparency Rule took effect. It mandates that the nation's 6,000 or so hospitals must reveal the confidential prices they have been charging different insurers and employers for 300 different tests and procedures—like MRIs, blood tests and surgeries. The data revealed so far are shocking: Not only do prices for the same test or procedure sometimes vary between hospitals in the same city by 1,000 percent or more, but some health plans are charged four or five or six times more for the same procedure at the same hospital.
