Carlsen F, Grytten J
Department of Economics, NTNU, Dragvoll, Norway.
Health Econ. 1998 Sep;7(6):495-508. doi: 10.1002/(sici)1099-1050(199809)7:6<495::aid-hec368>3.0.co;2-s.
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.
一些实证研究表明，人口与医生比例和医疗服务利用率之间存在负相关关系。然而，尚不清楚这种关系是反映了供方诱导、较低价格对患者需求的影响、对健康状况变化的供应反应，还是可得性的提高。在挪威，患者费用和国家报销费用是集中设定的。因此，利用率与人口与医生比例之间的相关性要么反映了供方诱导、供应反应，要么反映了可得性效应。我们应用了一个理论模型，该模型区分了诱导效应和可得性效应。该模型是在一个横断面数据集上实施的，该数据集包含了挪威所有按服务收费的初级保健医生的患者就诊和实验室检查信息。由于人口与医生比例可能是内生的，因此采用了工具变量法。我们没有发现无论是就诊次数还是实验室服务提供方面存在诱导效应的证据。
