Received: 29 July 2020
Accepted: 22 October 2020
First Online: 25 November 2020
Ethics approval and consent to participate
: Approval for the study protocol was obtained from the Institutional Review Board of Gangbuk Samsung Hospital (KBSMC 2018-01-036). And informed consent was waived by the board.
: Not applicable
: The authors declare that they have no competing interests.