The Dartmouth Atlas Project is run by the Center for Evaluative Clinical Sciences at Dartmouth Medical School. It's goal is to "accurately describe how medical resources are distributed and used in the United States." Using information compiled by the Centers for Medicare & Medicaid Services, the data covers hospitalizations of people aged 65 to 99 in the traditional Medicare system who are free to select any participating physician or hospital. Data is available from 1994-2003. [more]