Received: 19 December 2017
Accepted: 11 July 2018
First Online: 28 July 2018
Ethics approval and consent to participate
: This study was approved by the VGHKS and KMUH ethics committees [VGHKS17-CT4–20, KMUHIRB-SV(II)-20,170,003] and adhered to the ethical principles of the Declaration of Helsinki. The requirement for informed consent was waived by the institutional review boards of both participating hospitals.
: Not applicable.
: The authors declare that they have no competing interests.
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