Text and Data Mining valid from 2019-04-01
Received: 27 November 2018
Accepted: 7 March 2019
First Online: 1 April 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the institutional review board of the host hospital. (Kyowakai Research Ethics Board #16–02). Written informed consent to participate in the study was obtained from all the participants.
: Not applicable.
: The authors declare that they have no competing interests.
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