Funding for this research was provided by:
Hallym University (KR) Research Fund ((HURF-2017-42).)
Text and Data Mining valid from 2019-01-15
Received: 1 October 2018
Accepted: 4 January 2019
First Online: 15 January 2019
Ethics approval and consent to participate
: This study protocol was approved by the Hallym University Sacred Heart Hospital Institutional Review Board (IRB No. 2018–06-016). IRB approved this retrospective study, and informed consent was waived by the study subjects because all the patient data were anonymized and de-identified before the analysis.
: Not applicable.
: The authors declare that they have no competing interests in relation to the present work.
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