The Volume-Outcome Effect, Scale Economies, and Learning-by-Doing

摘要

There is a large empirical literature documenting the existence of a positive correlation between the number of times a hospital performs a given surgical procedure and the rate of good health outcomes achieved by patients at that hospital receiving that procedure. Typically, it is found that mortality is lower in hospitals that perform more of a given procedure. This result has been found for a wide variety of different procedures, time periods, and locations (David M. Shahian and Sharon L. Nor-mand, 2001; John D. Birkmeyer et al., 2002; Ethan A. Halm, 2002). The two leading explanations for this correlation are the "practice makes perfect" and "selective referral" effects (Harold S. Luft et al., 1987). In the practice-makes-perfect hypothesis, either learning-by-doing or quality-enhancing scale economies cause large hospitals to provide better quality care, improving outcomes. In the selective-referral hypothesis, hospitals with higher quality attract greater demand and therefore have a greater volume of patients.