Funding for this research was provided by:
Japan Primary Care Association (27-01-003)
Article History
Received: 29 September 2017
Accepted: 20 November 2018
First Online: 4 December 2018
Ethics approval and consent to participate
: The study protocol was approved by the institutional review board at Tsukuba University. It was explained to potential study participants that their participation was voluntary. Because of the anonymous nature of the study, we did not obtain written consent: filling out the questionnaire was considered to be a declaration of consent to participate.
: not applicable.
: The authors declare that they have no competing interests.
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