Jung, Minsoo https://orcid.org/0000-0003-3317-6507
Article History
Received: 21 August 2018
Accepted: 6 January 2019
First Online: 22 January 2019
Ethics approval and consent to participate
: Ethics and governance approvals were awarded by the Institutional Review Board, Korea Centers for Disease Control and Prevention (January 22, 2014; 20 140 122). In order to protect vulnerable research subjects, actual site interviews and investigations were performed after receiving written informed consent from the participants. During the investigation process, absolutely no information that could identify individual respondents was collected.
: Not applicable.
: The authors declared that they have no competing interests.