This study examines the relationship between supply of primary physicians and consumer satisfaction with access to, and quality of, primary physician services in Norway. The purpose is to throw light on a long-standing controversy in the literature on supplier inducement (SID): the interpretation of the positive association between physician density and per capita utilization of health services. We find that an increase in the number of physicians leads to improved consumer satisfaction, and that the relationship between satisfaction and physician density exhibits diminishing returns to scale. Our results suggest that policy-makers can compute the socially optimal density of physicians without knowledge about whether SID exists, if one accepts the (controversial) assumption that consumer satisfaction is a valid proxy for patient utility.
A number of empirical studies have shown that there is a negative association between population:physician ratio and utilization of medical services. However, it is not clear whether this relationship reflects supplier-inducement, the effect of lower prices on patient demand, a supply response to variation in health status, or improved availability. In Norway, patient fees and state reimbursement fees are set centrally. Therefore, the correlation between utilization and population:physician ratio either reflects supplier-inducement, a supply response or an availability effect. We applied a theoretical model which distinguished between an inducement and an availability effect. The model was implemented on a cross-sectional data set which contained information about patient visits and laboratory tests for all fee-for-service primary care physicians in Norway. Since population:physician ratio is potentially endogenous, an instrumental variable approach is used. We found no evidence for inducement either for number of visits or for provision of laboratory services.