4.3. Statistical analysis

Non-parametric tests were used in the statistical evaluation (I-III). The correlations were assessed with the Spearman correlation coefficient test (I-III). The differences between the groups were analysed with the Mann-Whitney U-test (I-III) or Fisher’s exact prob­ability test (II). P-values of 0.05 or less were considered significant. The statistical procedures were carried out using the SPSS for Windows® (SPSS Inc, Chicago, IL, USA).