Text and Data Mining valid from 2019-03-11
Received: 12 November 2018
Accepted: 6 March 2019
First Online: 11 March 2019
Ethics approval and consent to participate
: This retrospective study adhered to the tenets of the Declaration of Helsinki and was approved by the Institutional Review Board of Seoul National University Hospital (IRB No. 1807–139-961). The need for consent was waived by Institutional Review Board of Seoul National University College of Medicine. The administrative permission was required to access the raw data from Seoul National University Hospital and this permission was also granted by Institutional Review Board of Seoul National University College of Medicine (IRB No. 1807–139-961, Seoul, South Korea).
: Not applicable.
: The authors declare that they have no competing interests.
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