Kim, Dae-Hyun
Lee, Deok-Soo
Nah, Hyun-Wook
Cha, Jae-Kwan
Article History
Received: 9 November 2017
Accepted: 2 March 2018
First Online: 15 March 2018
Ethics approval and consent to participate
: Institutional Review Board of Dong-A University Hospital approved a request to waive of informed consent because it is not practicable to obtain consent from large numbers of patients for a retrospective chart review study, generally it also will not be appropriate to attempt to contact those patients to tell them about the study retrospectively. This study was approved by the Institutional Review Board of Dong-A University Hospital.
: Consent provided upon request.
: The authors declare that they have no competing interests.
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