Background: To drill down into why per capita health expenditures vary between the US and Japan, this exploratory study compares the price, volume and composition of services provided to inpatients for two procedures in an academic hospital in the US, and one in Japan. Methods: Detailed analysis of the amount reimbursed and services delivered was made from claims data for 449 acute myocardial infarction treated with coronary stents placed by percutaneous coronary intervention (PCI) and 115 heart valve dysfunction with heart valve replacement (HVR) cases in Johns Hopkins Hospital (JHH) Baltimore, Maryland, and 34 PCI and 21 HVR cases in Keio University Hospital (KUH), Tokyo. Results: After making appropriate adjustments, the reimbursed amount per discharge at JHH was significantly higher (Wilcoxon ranksum test, p < 0.01) for both medical conditions. This was due to more use of higher priced technology and higher prices for the same technology at JHH compared with KUH. However, medical imaging was performed more frequently at KUH and the reimbursed amounts per unit for the devices were higher at KUH. Analysis of room and board costs showed that the higher staffing level and wages of nurses at JHH was compensated by its shorter average length of stay for PCI, but not for HVR. Conclusion: Detailed analysis of the reimbursed amount and the utilization of services are needed to understand international variations in healthcare spending.
 OECD Health Data (2012) http://stats.oecd.org/index.aspx?DataSetCode=HEALTH_STAT
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