Funding for this research was provided by:
National Research Foundation of Korea (2017M3A9D8063538)
Text and Data Mining valid from 2018-07-31
Received: 23 January 2018
Accepted: 2 July 2018
First Online: 31 July 2018
Ethics approval and consent to participate
: Approval for this study was granted by the Boramae Hospital Review Board (IRB #: 26–2016-166). Since this study is retrospective and based on electronic medical record, need for consent was waived by Boramae Hospital Review Board (IRB #: 26–2016-166). No written or verbal consent was obtained from participants.
: Not applicable. Four cases in Table InternalRef removed were studied retrospectively, solely depended on electronic medical record. Hence, we have not obtained written consent of these cases.
: The authors declare that they have no competing interests.
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