Sasayama, Kensaku https://orcid.org/0000-0001-7474-9960
Adachi, Minoru
Article History
Received: 12 February 2019
Accepted: 30 April 2019
First Online: 7 May 2019
Ethics approval and consent to participate
: All participating children and their parents provided written informed consent before participation. The study was approved by the Institutional Review Board of Okayama University.
: Not applicable.
: The authors declare that they have no competing interests.