Funding for this research was provided by:
Korea University
Article History
Received: 1 November 2018
Accepted: 21 October 2019
First Online: 29 October 2019
Ethics approval and consent to participate
: This retrospective study got approved by the Institutional Review Board of Korea University Anam Hospital on February 12, 2018 (2018AN0037). Informed consent was waived by the IRB given that data were de-identified.
: Not applicable.
: The authors declare that they have no competing interests.