Received: 11 November 2020
Accepted: 18 March 2021
First Online: 29 March 2021
: This study was approved by the Institutional Review Board of the Korean Centers for Disease Control and Prevention and was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2013. All participants in this study conducted surveys and health examinations with informed consent.
: Not applicable.
: The authors declare that they have no competing interests.