Health care report cards. Validity of case definitions

Administrative databases are increasingly being used to construct health care report cards. We analyzed information from one of the original report cards, the Medicare Hospital Information Project. Assessment of mortality statistics for three clinical entities--coronary artery bypass surgery, hip reconstruction, and treatment of sepsis--demonstrated widespread outcome variances that reflected imperfect definitions rather than performance issues in clinical care. The use of administrative data sets to design report cards requires clinical expertise to ensure validity of the data. Designers of report card measures should share preliminary data with providers to enable feedback in methods and uncover definitional and validity concerns before widespread dissemination.