Statistical analysis
Statistical analysis was performed using the SPSS 16.0 (SPSS Inc.,
Chicago, IL) software. The Shapiro-Wilk test was used to test the
normality of data distribution. The independent sample t-test was used
for data with normal distribution; data shown as mean ± standard
deviation in the table. Numerical data without normal distribution were
analyzed using the Mann-Witney U test and shown as median
(maximum-minimum) values. Categorical data were analyzed using the
Chi-square and Fischer’s exact tests and shown as percentage (%).
Statistical significance was assessed as p-values <0.05.