STATISTICS
Analysis of the data was performed using SPSS v.17 statistical program
(SPSS Inc., Chicago, IL, USA). Continuous variables were presented as
mean ± standard deviation and categorical variables were expressed as
number (%). Comparative analysis was conducted Mann-Whitney U and
chi-square tests. Logistic regression analysis was performed to
determine the independent risk factors for mortality. p≤ 0.05 is
considered as statistically significant differences.