关键词: 医院, 医保部门, 单病种支付, 服务项目支付, 斯坦伯格博弈模型

Abstract: The difficulty and high cost in getting medical services have always been the main problems faced by patients in China. “Medicine feeds the doctor” system is one of the reasons for the high cost of medical treatment. In order to address the issue of expensive medical treatment, the Chinese government has introduced a series of policies, including single disease payment. Compared to the traditional fee for service, single disease payment limits the total payment of the type of disease. If the limit is exceeded when a patient receives treatment, the hospital will pay for the excess. However, if the cost of treatment is below the limit, then the hospital can make a profit. The purpose of single disease payment is to enable hospitals to control medical costs. However, many problems have also arisen in the implementation of single disease payment, such that hospitals refuse some critical patients in order to control costs, or some patients are required to be prematurely discharged, which greatly harms the interests of patients. Therefore, some scholars believe that fee for service has a better therapeutic effect on patients. Based on this, a comparative study is conducted on two payment schemes. By exploring their respective advantages and disadvantages, and comparing them, the improvement advice for single disease payment is given. This is of great significance for improving the medical quality and reducing medical expenses.
In this work we compare single disease payment with fee for service from 4 aspects: the effort made by the hospital to treat patients, the medical service pricing, the cost of treatment plan and the profits of the hospital. We first build a two-stage Stackelberg game model to study single disease payment. In this model, the medical insurance department first decides the medical service pricing to maximize the patients’ utility, then according to the decision of medical insurance department, the hospital decides the effort and treatment plan to maximize its profits. The backward induction method is employed to solve the model. Then we build a nonlinear optimization model to study fee for service. In this model, the hospital decides the medical service pricing and treatment effort to maximize its profits under some constraints. The model is transformed to a convex programing problem, KKT method is used to solve the transformed model, and the original model’s solution is obtained by solving the transformed model. We use the appendicitis as an example to do the numerical experiments. The data and calculation methods of some parameters are drawn from the literature. In the numerical experiments, two payment schemes are compared from optimal medical service pricing effort and profits of the hospital. Then the paper illustrates the impact of basis demand on the two payment schemes respectively and compares the two payment schemes under different values of basis demand. Last, the two payment schemes are compared when the hospital’s effort of single disease payment is equal to the optimal efforts of the hospital’s fee for service.
By solving the models, the results of two payment schemes are revealed. In the single disease payment scheme, the hospital chooses the treatment plan with minimal cost, the effort of hospital increases with the medical service pricing decided by medical insurance department, the medical service pricing increases with the minimal treatment costs and the lowest requirement of treatment quality, and decreases with basis demand of patients. However, fee for service makes the hospital choose the treatment plan with maximal cost, and the effort of hospital increases with the average maximal profit of treating a patient and basis demand of patients.
Through comparison between the two payment schemes, it is found that the 4 aspects of single disease payment are all less than those of fee for service. In addition, by improving the minimum requirement of the hospital’s effort of the single disease payment scheme, it can not only improve the hospital’s effort and increase the profits of hospital, but also control the treatment costs, making the single disease payment superior to fee for service. The results can provide policy reference for the medical insurance department to improve the medical quality of single disease payment. Besides, the single disease payment is the basis of diagnosis related groups payment, and the diagnosis related group payment is deemed as the main payment scheme in the future. However, it is currently still in the exploration stage, so this research can provide reference for it.

Key words: hospital, medical insurance department, single disease payment, fee for service, Stackelberg game model