Statistical analysis
SPSS.19 and R softwares statistical analysis was performed using the R Software. The measurement data were statistically described by mean ± standard deviation and performed by t test. Count data was described by frequency, and the chi-square test or Fisher’s exact test was used for the comparison between groups. Multivariable analyses to identify factors associated with death from COVID-19 patients were performed by cox proportional hazards regression model. P<0.05 was considered statistically significant.