Statistical Analysis
Statistical analyses were calculated with the Biometrical Analysis of
Sampling (BIAS 11.06 Software, Frankfurt, Germany). Categorical data
were presented as percentages. Continuous data were illustrated as mean
value ± standard deviation. Continuous and discrete variables are
expressed as mean ± SD or median and range for data not normally
distributed. Comparison of the two groups were analysed using the
chi-square test, Fisher´s exact test for qualitative data and
Mann-Whitney U test for quantitative data, respectively. Survival was
calculated applying the Kaplan-Meier estimates and additionally compared
with log rank test between the two groups. A p-value of less than 0.05
was defined statistically significant.