Statistical analyses
The analyses were performed on JMP 9.0 software (SAS Inc., Cary, NC,
USA). Continuous data were presented as median and standard deviation
(SD) or interquartile range (IQR). Categorical data were reported as
frequencies and percentages. Comparisons used the χ2 or Fisher’s exact
test for categorical variables and Student’s t test or
Mann–Whitney–Wilcoxon test, when appropriate, for continuous
variables. Survival curves were calculated using the Kaplan-Meier
method. A two-tailed p-value <0.05 was considered
statistically significant.