Received: 10 January 2018
Accepted: 7 May 2018
First Online: 21 May 2018
Ethics approval and consent to participate
: The Ethics Committee of Hiroshima International University (HIU) approved the research design of this study on September 3, 2014 (approval number 14–103). The participants were introduced to the study and briefed on the objectives. Verbal informed consent was obtained from all participants prior to the intervention. The Ethics Committee of HIU accepted verbal informed consent because of the non-sensitive nature of the study.
: The authors declare that they have no competing interests.
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