Kim, Myoung Jun
Lee, Jae Gil
Lee, Seung Hwan
Article History
Received: 7 August 2018
Accepted: 5 November 2018
First Online: 16 November 2018
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of Severance Hospital, Yonsei University Health System (4-2017-0545), which waived the requirement for informed consent because of the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.
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