Statistical analysis
Comparisons of demographic, clinical and chest X-ray imaging as well as outcomes of admissions were performed with appropriate univariate analyses. Specifically, nominal variables were compared using Pearson’s chi-square test, continuous variables that matched parametric criteria were compared by using Student’s t-test or One-Way ANOVA (analysis of variance), and ordinal variables and continuous variables that did not match parametric criteria were compared by using Wilcoxon or Mann-Whitney U tests. Continuous variables are presented as mean ± standard deviation (SD). Categorical data are expressed as percentages. Statistical significance was defined as p-value ≤ 0.05. Analyses were performed via IBM SPSS software version 22.