Text and Data Mining valid from 2018-04-23
Received: 1 March 2018
Accepted: 16 April 2018
First Online: 23 April 2018
Ethics approval and consent to participate
: All study participants provided informed written consent. The study protocol was approved by the Research Ethics Committee of our institution (reference number: 2018-[kenkyu01]-09). The research was conducted in accordance with the 1964 Declaration of Helsinki and its later amendments.
: All study participants provided informed written consent for publication.
: The authors declare that they have no competing interests.
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