Although there has been significant interest from health services researchers and policy makers about recent trends in hospitals' ownership of physician practices, few studies have investigated the strengths and weaknesses of available data sources. In this article, we compare results from two national surveys that have been used to assess ownership patterns, one of hospitals (the American Hospital Association survey) and one of physicians (the SK&A survey). We find some areas of agreement, but also some disagreement, between the two surveys. We conclude that full understanding of the causes and consequences of hospital ownership of physicians requires data collected at the both the hospital and the physician level. The appropriate measure of integration depends on the research question being investigated.
Keywords: hospital ownership of physicians; integration; organizations.