Text and Data Mining valid from 2019-01-16
Received: 12 September 2017
Accepted: 22 November 2018
First Online: 16 January 2019
Ethics approval and consent to participate
: The study was conducted at our hospital after approving by the institutional ethical committee of the Incheon St. Mary’s Hospital. Informed consent was not required for this retrospective study.
: Not applicable.
: The authors declare that they have no competing interests.
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