Ambulatory Surgery Centers: The Authors Respond

Abstract

Ambulatory Surgery Centers: The Authors Respond Larry Rabinowitz and Ronald W. Barnet raise three concerns about our article (Apr 2010). The first relates to the definition of ownership. Until direct measures of ownership are made publicly available, as we believe they should be, proxymeasures will have to suffice.We defined owners as surgeons who performed 30 percent or more of their outpatient procedures in a year at a specific ambulatory surgery center. This empirically derived measure is squarely based on current safe harbors under the federal anti-kickback statute, and it has been validated using an external data source. The second concern surrounds the appropriateness of the reported surgical trends. Unfortunately, the administrative data used in this study lack the clinical detail needed to discern the “right” rates of surgery. However, all of the procedures we examined are elective. As such, whether, when, where, and how to proceed are left to the physician’s discretion. Indeed, use of these procedures varies markedly, which suggests that the indications for intervention are not clear-cut. Further, clinical trial data suggest that someof theseprocedures afford the patient little or no benefit. A final concern pertains to the mechanism underlying the observed associations (that is, why do physician-owners do more surgeries?). We posit a variety of possibilities—both positive and negative—in the article. The true underpinnings are certainly multifactorial and are the topic of ongoing study. In the meantime, we encourage physician-owners to collect their data and disseminate the findings in the peer-reviewed literature, to allay concerns related to physician entrepreneurialism. John M. Hollingsworth University of Michigan ANN ARBOR, MICHIGAN