Funding for this research was provided by:
Ministry of Health and Welfare (1631200)
Received: 16 May 2018
Accepted: 31 August 2018
First Online: 14 September 2018
Ethics approval and consent to participate
: Approval for this study was obtained from the institutional review board of Seoul National University Hospital (IRB No. H-1802-069-922).
: Not applicable.
: The authors declare that they have no competing interests.
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