Article History
Received: 26 February 2020
Accepted: 30 June 2020
First Online: 11 July 2020
Ethics approval and consent to participate
: Prior to data collection, ethical approval for the study was obtained from the Kyushu University Institutional Review Board (IRB) for Clinical Research (#30–186). All children assented to participate in the survey, and informed consent was obtained from the children and their parents/guardians.
: No details of individual participants are described in this paper.
: The authors declare that they have no competing interests.