Econ Papers Daily / 期刊论文
医生作为说服者：来自中国医院的证据
Physicians as Persuaders: Evidence from Hospitals in China
摘要
I estimate a Bayesian persuasion model to examine how financial incentives and asymmetric information shape physician–patient interactions. This approach offers new insights into the role of insurance. First, the model predicts that patients' coinsurance moderates physicians' responsiveness to increases in service fees. This prediction is supported by a difference-in-differences analysis using Chinese health insurance claims data with random variation in physicians' reimbursement and patients' coinsurance rates. Second, the model implies that lower coinsurance rates reduce both patient price elasticity and skepticism, increasing the likelihood of physicians misdirecting patients toward unnecessary treatments. Using structural model estimates, I show that for a diagnosis where surgical treatment is discretionary, nearly half of the patients who received surgery would not have done so were they fully informed. Such misdirection from physicians is greater when coinsurance rates decrease, highlighting a new inefficiency channel beyond moral hazard. I decompose the effect of lowering coinsurance into moral hazard and the novel greater misdirection effect. Counterfactual analysis shows that, while patients benefit from lower out-of-pocket costs, greater misdirection nearly offsets these welfare gains.
中文摘要
我估计了一个贝叶斯说服模型，以考察经济激励和信息不对称如何塑造医患互动。这一方法为理解保险的作用提供了新视角。首先，模型预测患者的共付比例会调节医生对服务费用增加的响应程度。这一预测得到了基于中国健康保险索赔数据的双重差分分析的支持，该数据中医生报销比例和患者共付比例存在随机变动。其次，模型暗示较低的共付比例会降低患者的价格敏感性和怀疑程度，从而增加医生将患者误导至不必要治疗的可能性。利用结构模型估计，我表明对于手术属于可选择性治疗的诊断，近半数接受手术的患者若完全知情则不会选择手术。当共付比例下降时，医生的此类误导行为更为严重，这凸显了道德风险之外的一个新的效率损失渠道。我将降低共付比例的影响分解为道德风险和新的更大误导效应。反事实分析显示，尽管患者从较低的自付费用中获益，但更大的误导效应几乎抵消了这些福利收益。