Received: 17 November 2021
Accepted: 8 February 2022
First Online: 22 February 2022
: This study was approved by the Institutional Review Board of Korea University Anam Hospital (IRB number: ED17181). All data were anonymised; thus, the NHIS approved the study without requiring informed consent from each person.
: Not applicable.
: The authors declare that they have no competing interests.