Article History
Received: 26 November 2020
Accepted: 18 January 2021
First Online: 8 February 2021
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of Severance Hospital, Yonsei University Health System (4-2018-0114); the requirement for informed consent was waived because of the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.