Mr. Shinjiro Koizumi and some younger members of Japan's National Diet suggested a new policy, “Health Gold License” which would introduce financial incentives to encourage population health management, with people receiving medical checkups receiving a reduction in coinsurance from the current 30 percent to 20 percent. In this research, to evaluate the policy, we adjusted confounding factors of those insured who receive medical checkups (Medical-Checkup Group) and those who do not (Non-Medical-Checkup Group) using claims data, and estimated the effect of medical checkups on medical costs.

We analyzed Japanese employee-based claims data provided by the Japan Medical Data Center Co. Ltd. for the 3 million insured from January 2005 to December 2015. Two regression models were developed. Under model A, explanatory variables were year, age, dummy variables for various hierarchical condition categories and for medical checkups. Under model B, explanatory variables were estimated medical costs per patient per month (PMPM) in 2012 and a dummy variable for medical checkups. We also simulated the financial impact if Japan introduced Health Gold License for all insured.

The coefficients of medical checkups in model A and in model B were -JPY4,816 PMPM and -JPY8,735 PMPM, respectively. The gap of medical costs between the Medical-Checkup Group and Non-Medical-Checkup Group was JPY4,588 PMPM, without any adjustment. If all of those insured received medical checkups, the breakeven coinsurance would be 27.2 percent.

The Medical-Checkup Group is less expensive than Non-Medical-Checkup Group by at least 30%, therefore, the break-even coinsurance for them would be 0 percent. However, because most of those insured have already gone to medical check-ups every year, if the coinsurance were reduced from 30 percent to 20 percent for all insured, the finance would be largely negative. The break-even as 27.2 percent, we believe, would not incentivize the Non-Medical-Checkup Group to receive medical checkups. Therefore, the coinsurance reduction proposed under Health Gold License is not fully justified financially.