Received: 25 September 2017
Accepted: 25 February 2018
First Online: 22 March 2018
Ethics approval and consent to participate
: This study has been approved by the ethics committee of Kobe University Graduate School of Health Sciences (#579–1) and Kobe Kaisei Hospital (#0072), in accordance with the Declaration of Helsinki. Written informed consent was obtained from each patient before study enrolment.
: Not applicable.
: The authors declare that they have no competing interests.
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