Funding for this research was provided by:
Korea National Institute of Health (HI18C2383)
Received: 29 April 2020
Accepted: 22 July 2020
First Online: 7 August 2020
Ethics approval and consent to participate
: The study was approved by the institutional review board of Kyung Hee University Hospital, which waived the need for informed consent because of its retrospective nature.
: Not applicable.
: The authors declare that they have no competing interests.