Funding for this research was provided by:
National Research Foundation (2018R1D1A1B07049079)
Article History
Received: 5 September 2019
Accepted: 18 December 2019
First Online: 27 December 2019
Ethics approval and consent to participate
: This study was approved by the NHIS inquiry commission and adhered to the tenets of the Declaration of Helsinki for biomedical research. Informed consent was not required because the national insurance claim data were deidentification for the analysis. This study was also approved by the Institutional Review Board of The Catholic University of Korea (No. SC18ZESIO047).
: Not applicable
: The authors declare no competing interests.