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Article History

Received: 4 August 2021

Accepted: 26 December 2021

First Online: 9 January 2022

Declarations

:

: The authors declare that there is no conflict of interest.

: The Institutional Review Board at the Korea Centers for Disease Control and Prevention approved the protocol (IRB No. 2018-01-03-P-A). Ethical approval of participating hospitals was not required, because we used a publicly accessible database. This study was conducted in compliance with Declaration of Helsinki.

: All human and animal studies have been approved by the appropriate ethics committee and have therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.

: Written informed consent was obtained from all participants.