Funding for this research was provided by:
National Research Foundation (2018RICIB5086591)
Article History
Received: 20 September 2020
Accepted: 5 February 2021
First Online: 16 February 2021
Ethics approval and consent to participate
: This study was conducted in accordance with the Declaration of Helsinki. The KNHANES protocols were reviewed and approved by the Research Ethics Review Board of National Center fot Health Statistics. Written informed consents were obtained from all KNHANES participants. Data was provided in public without personal indentification information.
: Not applicable.
: The authors declare that they have no competing interests.