Manpower substitution and productivity in medical practice: review of research.

Probably in response to the often alleged physician shortage in this country, concerted research efforts are under way to identify technically feasible opportunities for manpower substitution in the production of ambulatory health care. The approaches range from descriptive studies of the effect of task delegation on output of medical services to rigorous mathematical modeling of health care production by means of linear or continuous production functions. In this article the distinct methodological approaches underlying mathematical models are presented in synopsis, and their inherent strengths and weaknesses are contrasted. The discussion includes suggestions for future research directions.