Park, Jungsun
Kim, Yangho
Article History
Received: 12 March 2020
Accepted: 7 April 2020
First Online: 27 April 2020
Compliance with Ethical Standards
: This survey was approved by the Institutional Review Board of the Korean Centers for Disease Control and Prevention (approval nos. 2013–07CON-03–4C, 2013–12EXP-03–5C).
: The authors declare that they have no conflicts of interest.
: All participants provided written informed consent.