Article History
First Online: 9 November 2019
Compliance with Ethical Standards
:
: The authors declare that they have no conflict of interest.
: This study was approved by the Korea University Hospital Institutional Review Board (IRB NO. 2015GR347). All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: All participants were given a description of the study, and we obtained the informed consent of both the adolescent and two guardians.