Reasons for referral among primary care and specialist physicians.

BACKGROUND: Specialty referral patterns can affect health care costs as well as clinical outcomes. For a given clinical problem, referring physicians usually have a choice of several physicians to whom they can refer. Once the decision to refer is made, the choice of individual physician may have important downstream effects. OBJECTIVE: To examine the reasons why primary care and specialist physicians choose certain specific colleagues to refer to and how those reasons differ by specialty. DESIGN: Cross-sectional Web-based survey supplemented with analysis of administrative claims data. PARTICIPANTS: A total of 616 physicians in office-based patient care specialties who were members of an academic physicians' organization and treated Medicare patients in 2006. MAIN MEASURES: A total of 386 respondents (63% response rate) were presented with a "roster" of other physicians' names with whom we predicted they had a relationship based on sharing Medicare patients. Among physicians in their "professional network" (consisting of any listed physician with whom respondents acknowledged a professional relationship), respondents reported if they referred to those physicians, and if so, provided up to two reasons why they referred to that particular colleague. Using logistic regression, we examined the likelihood that different specialists would endorse specific reasons for referring to chosen colleagues. KEY RESULTS: Primary care physicians (PCPs) initiated referrals to 66% of their "professional network" colleagues, while medical and surgical specialists initiated referrals to 49% and 52%, respectively (p