Text and Data Mining valid from 2018-11-01
Received: 19 July 2018
Accepted: 15 October 2018
First Online: 1 November 2018
Ethics approval and consent to participate
: The current research was approved from the Severance hospital institutional review board (protocol number 4–2018-0507).Informed consent from the participants was waived by the institutional review board as the current study satisfied all of the following requirements for the waiver of informed consent:The research involved no more than minimal risk to the participants (retrospective data analysis of previously collected medical records).
: Not applicable.
: The authors declare that they have no competing interests.
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