Identifying and measuring hospital characteristics using the SEER-Medicare data and other claims-based sources.

The context in which health care is delivered may have an impact on the outcomes and processes of care. Researchers analyzing claims data that reflect care rendered at many institutions may wish to identify hospital characteristics such as bed size, teaching status, degree of specialization, and case volume to evaluate their influence on outcomes. The authors describe the resources available from administrative data for characterizing hospitals. The article focuses on analyses using the SEER-Medicare-linked data, but has direct relevance for investigators working with other sources of claims data. First, the authors focus on assessment of hospital case volume, which is the principal hospital attribute that can be obtained directly from the SEER-Medicare data files. Second, they assess the information regarding hospital characteristics that can be gleaned from the American Hospital Association (AHA) survey and the annual cost reports submitted to the Center for Medicare and Medicaid Services (CMS) by all certified hospitals. From a comparison of the responses of 4,434 hospitals to 1994 AHA and CMS surveys, the authors conclude that the two data sources contain very similar information, but that for most investigators, use of data from CMS cost reports will be preferable to use of AHA data because of higher survey-completion rates and public availability.