Article History
Received: 7 April 2019
Revised: 26 July 2019
Accepted: 27 July 2019
First Online: 5 August 2019
Compliance with Ethical Standards
:
: The authors declare that they have no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. For this type of study, formal consent is not required.
: This study has obtained IRB approval from Asan Medical Center Institutional Review Board, and the need for informed consent was waived.
: Consent for publication was obtained for every individual person’s data included in the study.