Text and Data Mining valid from 2018-04-27
Received: 11 September 2017
Accepted: 16 April 2018
First Online: 27 April 2018
Ethics approval and consent to participate
: This study was conducted with the approval of the University of Toyama’s ethics committee. The consent to participate was given in written format. The consent for those participants with cognitive impairment were provided by their family members or proxies.
: The authors declare that they have no competing interests.
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