The volume and mix of inpatient services provided by academic medical centers

This is the first in a series of AAMC Papers that analyze the clinical spectrum of patients treated in the nation's teaching hospitals. As stated in the separate Introduction, "The Transformation of Data into Knowledge," subsequent papers will examine trends in the provision of care to the indigent and make comparisons of quality of care among teaching and non-teaching hospitals. These analyses, carried out by the AAMC's Center for the Assessment and Management of Change in Academic Medicine (CAMCAM), are made possible by a reorganization of the AAMC's information infrastructure, in which many formerly separate databases have been linked. The Introduction concludes with a description of specific AAMC-CAMCAM initiatives that are being planned. This initial analysis examines the volume and mix of clinical services provided by AMCs, examines trends in these services over time, and compares services provided at different AMCs, in different markets, and between AMCs and non-teaching hospitals. Data from a variety of sources were used in these secondary analyses. The American Hospital Association's Annual Survey of Hospitals database was used to analyze volumes of inpatient services provided in AMCs and other hospitals. The AAMC's Clinical-Administrative Data Service database was used to analyze the volume and mix of clinical services provided in individual AMCs. The Agency for Health Care Policy and Research's Nationwide Inpatient Sample was used to compare the mix of clinical services provided in AMCs and other hospitals. Volumes of inpatient services in AMCs changed little between 1991 and 1994 and totaled six million hospitalizations, 41 million inpatient days, and two million inpatient surgeries in 1994. The mix of inpatient services in AMCs also showed little variation over time among individual AMCs, in markets with both high and low managed care penetrations, between public and private AMCs, or between AMCs and non-teaching hospitals, with the ten most frequent diagnoses accounting for significant proportions of total services. In contrast, several specialized services were much more likely to be offered and provided by AMCs. Despite rapid change in the health care environment, the volume and mix of clinical services provided by AMCs have been relatively stable. Implications for hospital planners, service chiefs and administrators, medical educators, clinical investigators, and health policymakers are discussed.