Statistical Analysis
Continuous data are presented as mean ± standard deviation (SD) or as
median (interquartile range). Categorical data are summarized using
absolute values (percentage). Continuous variables were tested for
normal distribution with the Shapiro-Wilk test. Non-continuous variables
expressed as proportions were compared with using χ 2analysis or Fisher’s exact test, as appropriate. Intergroup comparisons
were performed using a the 2-tailed Student t test (continuous
variables) or the χ2 test/Fisher test (categorical variables) for
unpaired data. Paired non-parametric exact methods were used to compare
the change in QoL over time for each patient. Long-term survival was
described with the Kaplan–Meier method, and comparisons were made by
use of the log-rank statistic. All P-values were two-sided, with a
P-value of < 0.05 was considered to indicate statistical
significance.