Statistical Analysis
Data descriptive analysis was carried out using Microsoft Excel®, and
statistical analysis was performed using SPSS software. We evaluated
discrete variables to determine the risk factor for short-term mortality
in COVID-19 patients with and without comorbidities. The t-test,
Mann-Whitney test, and χ2test statistics were used to determine
differences in study variables between groups. We used Cox proportional
hazard models to determine whether comorbidities were predictive of
in-hospital mortality. A proportional subdistribution hazards model
analysis was utilized, in which death is represented as a competing
risk. The univariate models’ significant predictors were then included
in multivariate models, adjusting for possible confounding variables.
The proportional hazard assumption was tested for all reported
variables. Odds ratios with 95% confidence intervals were obtained. A
two-sided p-value of 0.05 was considered statistically significant.