Funding for this research was provided by:
National Research Foundation of Korea (NRF-2018R1A5A2025079)
Received: 26 May 2020
Accepted: 5 August 2020
First Online: 14 August 2020
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Severance Hospital (4–2017-0673). The need for patients’ written informed consent was waived, as this was a retrospective study.
: Not applicable.
: The authors declare that they have no competing interests.