Article History
Received: 1 October 2018
Accepted: 28 December 2018
First Online: 10 January 2019
Ethics approval and consent to participate
: After obtaining approval from the Severance Hospital Institutional Review Board (IRB number: 4–2008-0583), the trial was performed at Yonsei University Severance Hospital. The written informed consent was obtained from all subjects participating in the trial.
: Not applicable.
: The authors have no conflicts of interest.
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