1.   The Mann-Whitney U rank sum test and Spearman rank correlation test were used for statistical evaluation.

2.   Differences between groups were compared using a Wilcoxon rank sum test.

3.   Statistical analysis was performed by means of the Wilcoxon rank sum test for paired data.

4.   This difference, however, did not reach statistical significance with the signed rank sum Wilcoxon test.

5.   Evolution of ordered categorical data in each group was assessed by the Wilcoxon rank sum test.

6.   Differences between the groups were determined by Wilcoxon rank sum test.