Funding for this research was provided by:
National Research Foundation of Korea (2017R1D1A1B03032985)
Text and Data Mining valid from 2018-09-20
Received: 23 April 2018
Accepted: 13 September 2018
First Online: 20 September 2018
Ethics approval and consent to participate
: This study received ethical approval from the Institutional Review Board of the Seoul National University Hospital. The Ethics Committee study protocol number was 1706–205-866 and the IRB granted a waiver of consent for this retrospective chart review study.
: Not applicable.
: The authors declare that they have no competing interests.
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