The Theoretical and Experimental Study on Selection by Patients and Medical Physicians under The Payment System for Reimbursement to Medical Institutions

本研究的目的是考察在保证固定治疗水平的前提下，降低医疗费用总额对按服务付费（FFS）和预期付费（PPS）并存的医疗机构报销支付制度的影响。本研究首先建立了患者可以自由选择医疗机构的理论模型，然后用实验经济学的方法对这些理论假设进行了检验。以下三点可以作为研究的结果。在将医疗服务分为医生治疗等“面对面服务”的医疗服务和检查等“定型服务”的医疗服务的情况下，报销的差异对两种医疗服务都有影响，无论利润还是患者利益最大化。定型服务的供给大于面对面服务，是造成医疗服务供给过剩和不足的主要因素。在PPS模式下，医疗机构为了保证必要的最小利润，在医疗机构的治疗水平选择上，面对面服务治疗的水平高于患者的疾病水平。此外，观察患者向其他医疗机构的引荐行为是否存在引入中等程度疾病患者的可能性。对于病情严重的病人，很明显，经常进行介绍行为。如果一种疾病的单位奖励由总报销金额除以总请求分数决定，则医疗机构表现为古尔诺-纳什竞争。随着医疗机构数量的增加和竞争的加剧，该病的社会总治疗水平也在提高。

The purpose of the research is to inspect how the reduction of the total medical expenses with securing a fixed treatment level influence on the Payment System for reimbursement to medical institutions which fee-for-service payment (FFS) and prospective payment (PPS) coexist. In this research, the theory model which patients can choose medical institutions freely is built first, and then those theory suppositions are investigated by the experimental economics method. Three points to mention in the following can be shown as the research result.1.In the case that medical service was divided into the medical service concerned with the "face-to-face service" such as treatment by the doctor and the "stereotyped service" such as inspection, the difference in the reimbursement has impact on two medical services regardless of the profit or the patient's benefit maximization. The stereotyped service was supplied more than the face-to-face service, and was the main factor in the over- and under- supply of medical service.2.In the treatment level choice of the medical institution which tries to secure the necessary minimum profit under PPS, the level of the face-to-face service treatment was higher than patient's disease level. Moreover, the patient introduction behavior to other medical institutions was observed the possibility to introduce the disease patient of the middle degree. For the serious disease patient it became clear that the introduction behavior was done frequently.3.If a unit reward of one disease was decided by dividing total amount of reimbursement by the total request score and medical institution behaved Cournot-Nash competition. The social total treatment level of this disease rose as the number of medical institutions increased and competition was promoted.