Funding for this research was provided by:
Japan Society for the Promotion of Science (09J07360, 25560386)
Received: 13 March 2018
Accepted: 10 April 2019
First Online: 30 April 2019
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of Life Ethics, Graduate School of Medicine, Kumamoto University (Nos. 285 and 313) and was conducted in accordance with the Declaration of Helsinki. Guardians of all participants provided written informed assent and consent for participation in this study.
: Not applicable.
: Author Akemi Tomoda is currently acting as an Associate Editor for BMC Psychiatry. All other authors declare that they have no competing interests.
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