Statistical analysis:
Data normality was assessed by Kolmogorov-Smirnov test. Quantitative
comparisons without a normal distribution were carried out using
Mann-Whitney and Kruskal Wallis-tests. Comparisons of qualitative
variables were performed using the X2 test. Receiver
operating characteristic curves (ROC curves) were performed for getting
cut-off point to indicate positive results. P-values less than 0.05 were
considered statistically significant.