Funding for this research was provided by:
Ministry of Science and Technology (22590452)
Text and Data Mining valid from 2018-03-27
Received: 7 February 2017
Accepted: 19 March 2018
First Online: 27 March 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the Faculty of Medicine of the University of Tsukuba. The purpose of this study and measures to ensure secure data management were stated on the first page of the questionnaire. The researchers received written consent from the participants for participation in this study.
: Not applicable.
: The authors declare that thay have no competing interests.
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