Text and Data Mining valid from 2019-08-28
Received: 6 March 2019
Accepted: 19 August 2019
First Online: 28 August 2019
Ethics approval and consent to participate
: As the following study was performed retrospectively, formal consent was not required. The name of the Board: Institutional Review Board of Inha University Hospital. The approval number is INHAUH, 2016-12-003.
: Not applicable.
: The authors declare that they have no competing interests.