Funding for this research was provided by:
Grants-in-Aid for Research on Policy Planning and Evaluation (H26-SEISAKU-SITEI-011)
the 19th Grant of the Institute for Health Economics and Policy
Received: 16 January 2018
Accepted: 19 February 2018
First Online: 1 March 2018
Ethics approval and consent to participate
: The Tokyo Medical and Dental University ethics committee approved this study and waived the requirement for informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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