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).