This study investigates the impact of a Japanese public health care reform—called the contract out policy—on intergenerational inequality and the probability of a surplus in medical saving accounts. First, I investigate the change in the lifetime net burdens for each generation and public health expenditures and conduct simulation analyses to consider the effects of contracting out public health insurance on intergenerational inequality using the generational accounting method. Next, I simulate the probability of a surplus in medical savings accounts using the transition probability of health care expenses based on individual health data, such as receipt data. According to the simulation results, the net lifetime burden on future generations after contracting out shows a 1% reduction compared to the base case, which is not implemented in public health care reform. In addition, the probability of medical savings accounts remaining in surplus, including cases of zero medical expenses, is 69.6%.

这项研究调查了日本公共卫生保健改革（称为外包政策）对代际不平等的影响以及医疗储蓄账户出现盈余的可能性。首先，我调查了每一代人的终生净负担和公共卫生支出的变化，并进行了模拟分析，以考虑使用世代核算方法将公共健康保险外包对代际不平等的影响。接下来，我使用基于个人健康数据（例如收据数据）的医疗保健费用的转移概率来模拟医疗储蓄账户中出现盈余的概率。根据仿真结果，外包后，子孙后代的净寿命负担比基本情况减少了1％，在公共卫生保健改革中没有实施。此外，医疗储蓄账户剩余（包括零医疗费用的情况）的可能性为69.6％。