Risk stratification is a statistical process by which quality of care can be assessed independently of patient case mix. The evaluation of risk-adjusted patient outcome has become an important part of managed care contracting in some markets, and risk-adjusted outcome rates for hospitals are being reported more frequently in the popular press and on the Internet. This book, written by a statistician and two surgeons for a clinical audience, is a practical guide to the process of risk stratification and does not require or assume an extensive mathematical background. It describes the rationale and assumptions for risk stratification, and provides information on evaluating the quality of various published risk-stratification studies. Numerous practical examples using real clinical data help to illustrate risk stratification in health care. The volume also serves as a step-by-step guide to the production and dissemination of risk-adjusted outcome results for local programs.