Can preventing diversion of profitable patients justify hospitals' economic credentialing under the antitrust laws?

Investments by physicians in specialty hospitals, ambulatory surgery centers, and other competing facilities have caused many full-service acute care hospitals a great deal of concern. These full-service hospitals believe they are at a disadvantage in competing against such centers because physician-investors allegedly can "pre-select" profitable patients. Full-service hospitals have reacted in a variety of ways, including adopting economic credentialing policies. Physician-owned centers often view these policies as anti-competitive and seek relief under the antitrust laws. Hospitals attempt to defend these actions on the grounds that they prevent what economists call "free-riding." A key element of this defense is whether pre-selection is occurring and whether the hospital has sufficient evidence of pre-selection to justify the conduct under the antitrust laws.