Sawa, Satomi http://orcid.org/0000-0002-9284-6438
Sekine, Michikazu
Yamada, Masaaki
Fukazawa, Yugo
Hiraku, Yusuke
Article History
Received: 17 April 2020
Accepted: 1 September 2020
First Online: 14 September 2020
Ethics approval and consent to participate
: The survey was approved by Ethics Committee of University of Toyama (H28-137). Written informed consent was obtained from all the schoolchildren and their parents, and participation was voluntary.
: N/A
: The authors declare that they have no competing interests.