Statistical analysis
All analyses were performed on SPSS v21 (SPSS Inc., Chicago, IL, USA).
For the normality check, the Kolmogorov-Smirnov test was used. Data are
given as mean ± standard deviation or median (1st quartile - 3rd
quartile) for continuous variables according to normality of
distribution, and as frequency (percentage) for categorical variables.
Repeated measurements were analyzed with the Friedman’s analysis of
variances by ranks since parametric test assumptions were not met.
Post-hoc pairwise comparisons were performed with the Bonferroni
correction method. Multiple linear regression analysis (stepwise
selection method) was performed to determine significant factors
associated with outcomes. p<0.05 values were accepted as
statistically significant results.