Abstract: Excessive medical treatment has negative effects on the overall social and economic development. This paper takes the suppliers and the demanders excessive medical treatment into a framework of budget constraint, and studies the inner logic and the transfer mechanism in it. The result shows that the cause of China's excessive medical problems stems from changes in the external environment that leads to the hardening of the budget constraints of medical service providers and changes the behavior of related groups in the supply side, thus produces motivation to maximize medical income. The changes enables the medical service demander to soften budget constraint and have freedom choice based on it, thus produces motivation to maximize medical benefits. The problem of excessive medical governance is essentially the principalagent and mechanism design issue under asymmetric information conditions. Therefore, incentive regulation based on excessive medical governance is a breakthrough to effectively solve the problems.

Key words: Key words: excessive medical treatment, budget constraint, incentive regulation

摘要： 过度医疗问题对我国社会经济发展产生了较大负面效应。本文将医疗供需双方的过度医疗行为纳入预算约束分析框架，并分析其内在逻辑和传递机制。结果表明：中国过度医疗问题的根源，首先在于医疗服务供方预算约束的硬化及其内部利益相关者的行为变化，由此产生医疗收入最大化动机。其次在于医疗服务需方能够实现预算约束的软化及其基础上的自由选择，由此产生医疗福利最大化动机。过度医疗问题的治理本质上为信息不对称条件下的委托—代理和机制设计问题。医疗行业的激励性规制是解决这一问题的突破口。

关键词: 过度医疗, 预算约束, 激励性规制