Funding for this research was provided by:
Pfizer Health Research Foundation
Received: 16 January 2018
Accepted: 8 April 2019
First Online: 6 June 2019
Ethics approval and consent to participate
: Ethical approval and the consent by the participants were waived by the ethics committee of Teikyo University for this study, which used open access, anonymized statistical and epidemiological information.
: Not applicable.
: The authors declare that they have no competing interests.
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