Funding for this research was provided by:
National Research Foundation of Korea (2017R1C1B5017513)
Text and Data Mining valid from 2018-04-26
Received: 15 January 2018
Accepted: 17 April 2018
First Online: 26 April 2018
Ethics approval and consent to participate
: This study was approved by the Yonsei University Health System Institutional Review Board (2017–0186-001). Informed consent was waived from the Yonsei University Health System Institutional Review Board since patients’ information was collected during the routine clinical practice and patients were identified by anonymized investigator-generated code not linkable to their personal data. The same Institutional Review Board granted access to the institutional databases used in this study.
: The authors declare that they have no competing interests.
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