Funding for this research was provided by:
Seoul National University Hospital (2013-2425)
Text and Data Mining valid from 2018-04-16
Received: 4 September 2017
Accepted: 3 April 2018
First Online: 16 April 2018
Ethics approval and consent to participate
: The institutional review board of Seoul National University Hospital reviewed the study protocol and provided study approval. It waived the requirement for written consent (IRB registration number 1407–043-593).
: The authors declare that they have no competing interest.
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