1.6 Statistical Analysis
Statistical analyses were performed using SPSS (v. 19.0) software with an α of 5%. The measurement data are presented as mean ± standard deviation or median (interquartile range [IQR] P25, P75). Comparisons between two groups were made using a T-test and Wilcoxon’s rank sum test. Enumeration data are expressed as percentages using the χ2 test.