Should physicians' dual practice be limited? An incentive approach.

We develop a principal-agent model to analyze how the behavior of a physician in the public sector is affected by his activities in the private sector. We show that the physician will have incentives to over-provide medical services when he uses his public activity as a way of increasing his prestige as a private doctor. The health authority only benefits from the physician's dual practice when it is interested in ensuring a very accurate treatment for the patient. Our analysis provides a theoretical framework in which some actual policies implemented to regulate physicians' dual practice can be addressed. In particular, we focus on the possibility that the health authority offers exclusive contracts to physicians and on the implications of limiting physicians' private earnings. Copyright 2004 John Wiley & Sons, Ltd.