If you need a new pair of sandals, any smart shopper can find out if the neighborhood shoe store is more or less expensive than the department store downtown. A small amount of research can help a consumer compare prices on just about any good or service in America. The exception: health care.

Health care costs in America are such a mystery that often even doctors and most people who work in hospitals or clinics don’t know what they’re charging. In a new commentary, Robert Graham, MD, National Program Director for AF4Q, and Michael W. Painter, JD, MD, Senior Program Officer at the Robert Wood Johnson Foundation, offer their thoughts on the complex landscape of measuring health care cost and determining price in America.