Article History
Received: 31 May 2018
Accepted: 30 October 2018
First Online: 10 November 2018
Ethics approval and consent to participate
: This retrospective cohort study protocol was approved by the Institutional Review Board of Kyushu University Hospital in March 2018 (IRB# 29–630).The IRB waived the need for written informed consent from participants because all patients received usual care and were not subjected to research activities.
: Not applicable.
: The authors declare that they have no competing interests.
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