Physician resource planning in an era of uncertainty and change

Depending upon one's perspective, physicians may be viewed as the "cost drivers" and principal contributors to unnecessary care and the waste of resources, or as the players best able to enhance access to underserviced areas and improve health outcomes in a population. Given these extreme and unrealistic perspectives, it is no wonder that so much energy has been put into determining the optimal supply of physicians, and, once such determinations are made, finding the combination of market-based or regulatory pressures most likely to achieve the desired goal. In addressing the issue of physician workforce planning it is important to understand the limitations of physician numbers alone as a determinant of population health outcomes. However, given the substantial direct and indirect public financing of physician training and practice, an understanding of workforce requirements is essential for public accountability. Various approaches have been used to determine the number of physicians needed in a particular area. Needsbased planning uses expert panels to estimate the number of physicians needed per capita to treat the diseases managed by a particular specialty.3 An adjusted needs model is a modification of this; it takes into consideration the fact that some illness does not require the services of a physician, and that only a fraction of all illness can be expected to be identified and managed by health care providers.2 Demand-based planning uses current utilization patterns as an indicator of future workforce requirements and typically ignores the evidence that, in noncapitated markets, an increased supply of medical resources leads to increased demand and utilization. (This is explained in part in terms of supplier-induced demand or the hypothesis that physicians adjust their practices to reach a target income.4,5) The main drawback common to these approaches is that they may not fully take into account the possibility and implications of fundamental change in the health care system. From a plethora of studies on future physician supply needs in the US, there emerged virtually no signal of the current high demand for primary care physicians and physician substitutes, and the accompanying reorientation toward primary care of many specialists.6 Similarly, there was no indication that the US would require additional infectious disease specialists and researchers to cope with the unforeseen and devastating epidemic of HIV/AIDS.