Funding for this research was provided by:
Japan Society for the Promotion of Science (15K08729)
Received: 20 March 2018
Accepted: 17 July 2018
First Online: 7 August 2018
Ethics approval and consent to participate
: The Shika study protocols were approved by the Kanazawa University Ethical Committee (No.1464). Written informed consent was obtained from the guardians of all participants prior to data collection.
: Not applicable
: The authors declare that they have no competing interests.
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