Funding for this research was provided by:
National Research Foundation (2017R1D1A1B03032985)
Article History
Received: 29 September 2018
Revised: 2 December 2018
Accepted: 10 December 2018
First Online: 13 March 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. The Institutional Review Board of Seoul National University Hospital in South Korea granted a waiver of consent for this retrospective chart review study.