2.3 Statistical analyses
Continuous variables were described through median and interquartile ranges (IQR) values, and categorical variables were presented as frequencies and percentages (%). Two-tailed t test and Mann-Whitney U test were used, as appropriate, to compare the data from two groups. The rates of categorical parameters in two different groups were compared by chi-square test and Fisher’s exact test, as appropriate. Spearman’s correlation test was applied to calculation of the correlation coefficients between different variables. A test with p value of less than 0.05 was considered statistically significant. All statistical analyses were performed by GraphPad Prism 8 (GraphPad Software Company).