Research Article

Correlation of Low Levels of α-1 Antitrypsin and Elevation of Neutrophil to Lymphocyte Ratio with Higher Mortality in Severe COVID-19 Patients

Figure 1

Flow chart of case enrolment in this retrospective observational cohort study between July 2020 and November 2020. Abbreviations: AAT: alpha-1 antitrypsin; NLR: neutrophil-lymphocyte ratio; PCR: polymerase chain reaction.