Funding for this research was provided by:
Ministry of Education, Culture, Sports, Science and Technology (17H04141)
Japan Agency for Medical Research and Development
Research on Policy Planning and Evaluation from the Ministry of Health, Labour, and Welfare, Japan (H29-Policy-Designated-009, H29-ICT-Genral-004)
Received: 29 November 2016
Accepted: 24 August 2017
First Online: 2 September 2017
Ethics approval and consent to participate
: Conduct of the study was approved by the Institutional Review Board of The University of Tokyo, which waived the requirement for informed consent owing to the anonymity of the data. Approval for the use of the data was obtained from the Diagnosis Procedure Combination Study Group.
: Not applicable.
: The authors declare that they have no competing interests.
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