Acknowledgments
We acknowledge all the health-care workers involved in the diagnosis and
treatment
of COVID-19 patients in South Korea. We thank Korea Disease Control &
Prevention Agency, National Medical Center and the Health Information
Manager in
hospitals for their effort in collecting the medical records. This study
was supported by a grant from the National Research Foundation of Korea
(NRF) grant funded by the Korea government (MSIT)
(NFR-2017R1C1B5076565).