Funding for this research was provided by:
Seoul National University Hospital (03-2014-0440)
Korea Health Industry Development Institute (HI14C1277, HI13C2163)
Text and Data Mining valid from 2019-05-06
Received: 5 March 2019
Accepted: 26 April 2019
First Online: 6 May 2019
Ethics approval and consent to participate
: The study protocol was reviewed and approved by the institutional review board of SNUH [H-1210-016-430]. This study was carried out in accordance with the recommendations of the Declaration of Helsinki for biomedical research involving human subjects. In accordance with South Korea regulation, retrospective studies without any additional therapy or monitoring procedure, do not need formal written consent from patients. Because the study was retrospective designed without any investigational intervention, the study-specific informed consent was not obtained from each patient. (ExternalRef removed, ExternalRef removed).
: Not applicable.
: The authors declare that they have no competing interests.
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