Our mission is to identify such centers. The first standard a hospital has to meet is to be a member of the Council of Teaching Hospitals, to be affiliated with a medical school, or to have at least nine out of 17 prescribed technological services. This year that winnowed the field to 1,701 centers. To be eligible for ranking in 13 specialties, a hospital then had to perform a certain number of defined procedures over three years or be identified as an outstanding facility in U.S. News physician surveys. The specialists are chosen at random from the American Medical Association database of all 711,749 U.S. physicians.
Scores show the percentage of survey respondents who named the hospital over the past three years.
The ratios compare actual deaths with the number expected, factoring in severity of condition. Sachs Group, an Evanston, Ill., supplier of health and other data, calculated the ratios, adjusting them by using a 3M Health Information Systems software program called All Patient Refined Diagnosis Related Group. Most remaining data come from annual American Hospital Association surveys. Kidney disease appears this year as a 17th specialty. The techniques used to process the raw mortality numbers also were revised so that mortality, reputation, and the group of other factors are now calculated in the same way.