Funding for this research was provided by:
Seoul National University Hospital (No. 06-2014-015)
Ministry of Health and Welfare (HC15C1507)
Received: 18 February 2020
Accepted: 11 June 2020
First Online: 22 June 2020
Ethics approval and consent to participate
: The study protocol was approved by the institutional review boards of Seoul National University Bundang Hospital, Seoul National University, Samsung Medical Center, Asan Medical Center, Pusan National University Yangsan Hospital, Hallym University Sacred Heart Hospital. The need for informed consent was waived due to the retrospective design of the study.
: Not applicable.
: The authors declare that they have no competing interests.