Funding for this research was provided by:
a Grant-in-Aid from the Ministry of Health, Labour and Welfare, Health and Labour Sciences Research Grants, Japan (H23-TokubetsShitei-002, H24-Kenki-Shitei-001, H25-Kenki-Shitei-001(Fukkou))
Received: 26 September 2017
Accepted: 28 May 2018
First Online: 4 June 2018
Ethics approval and consent to participate
: In the present study, participants provided written informed consent for participation and publication. This study was approved by the Institutional Review Board of Iwate Medical University.
: The authors declare that they have no competing interests
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