Funding for this research was provided by:
VLIR-IUC Program Hue University
Article History
First Online: 9 January 2020
Compliance with Ethical Standards
:
: No conflict of interest in whatever form exists related to this study, for none of the authors. Moreover this study was not submitted before nor is it under consideration for publication elsewhere.
: Ethical approval for this study was obtained from Institutional Ethical Committee of Hue University.
: “Active informed consent was obtained (1) the director of the Education and Training Department of Hue City, (2) the concerned school authority in line with formal regulations, and (3) from the participating adolescents themselves. See the original used informed consent form for adolescents (in Vietnamese<b>)</b> on the supplementary document.
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