Park, Eun-Young
Article History
Received: 26 October 2017
Accepted: 5 April 2018
First Online: 19 April 2018
Ethics approval and consent to participate
: Informed consent was obtained from the parents of all children, as parents of children below 15 years of age are their legal representatives. Ethical approval for this study was granted by the Ethics Committee of Jeonju University.
: The author declares no competing interests.
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