تقسیم کار پزشک و انتخاب بیمار برای اقدامات سرپایی

Little is known about the ability of incentives to influence decisions by physicians regarding choices of settings for care delivery. In the context of outpatient procedural care, the emergence of freestanding ambulatory surgery centers (ASCs) as alternatives to hospital-based outpatient departments (HOPDs) creates a unique opportunity to study this question. We advance a model where physicians’ division of labor between ASCs and HOPDs affects the medical complexity of patients treated in low-acuity settings (i.e. ASCs). Analyses of outpatient surgical procedure data show that physicians working exclusively in low-acuity settings (i.e. ASCs) treat patients of significantly higher medical complexity in these settings than do physicians who also practice in higher-acuity settings (i.e. HOPDs). This discrepancy shrinks with increasing procedural risk and with increasing distance between ASCs and acute care hospitals.

The motives and ability of physicians to influence the medical services used by their patients have received much attention in the health economics literature (Arrow, 1963 and McGuire, 2000). Seminal work in this area has focused on demand inducement, where financial incentives may increase the quantity of services recommended and delivered by physicians beyond the point at which the medical benefits of such services justify their costs ( Evans, 1974 and McGuire and Pauly, 1991; Labelle et al., 1994 and Gruber and Owings, 1996). Prior work on referrals by physicians for office- versus hospital-based care has highlighted the effects of financial incentives on decisions regarding the utilization of resources for the care of acute conditions ( Marinoso and Jelovac, 2003, Blomqvist and Léger, 2005, Bian and Morrisey, 2007 and David and Helmchen, 2011). However, little attention has been paid to incentives that may influence decisions regarding the choice of setting for otherwise identical medical procedures in cases where such choices may influence patient outcomes.

Our findings indicate that patients with higher medical complexity are more likely to receive treatment in HOPDs (as opposed to ASCs). Further, we find that patient selection for ASC care is potentially sensitive to differences in the opportunity cost of HOPD referral, as identified by variations in physician division-of-labor, patient complexity, and ASC location. Within ASCs, those physicians who work exclusively at ASCs tend to take on more risk compared to their splitter counterparts. This behavior weakens as (1) the ASC is located further away from emergency capabilities, (2) patients are over 65, and (3) procedures are more risky. The effects we observe persist despite adjustment for patient characteristics, secular time, physician characteristics, county fixed effects, and when using an instrument for splitting status to mitigate concerns regarding omitted variable bias. Further, these effects persist in samples defined through a variety of procedure and patient-based exclusion criteria, and are robust to a range of alternate definitions of key variables. In all these cases, we identify a group of patients with a level of surgical risk that would prompt treatment at an HOPD by a splitter, while a non-splitter would treat these patients at an ASC.