Funding for this research was provided by:
ministry of health & welfare, republic of korea (HI19C1202)
Received: 26 June 2021
Accepted: 12 October 2021
First Online: 27 October 2021
: As the databases extracted from NHIS could not be identified directly or through identifiers linked to the subjects, therefore, our study was exempted by the Institutional Review Board (IRB) of Hanyang University Hospital (IRB file NO. HYUH 2018-04-030).
: Not applicable
: YKS has received research grants from Bristol-Myers Squibb, Eisai, Pfizer and JW Pharmaceutical. JYH, HK, SYJ, EJJ and SKC have nothing to declare.