Statistical analyses
All statistical analyses were performed with JMP Pro, Version 14 (SAS
Institute Inc., Cary, NC, 1989–2007). Mean values and standard
deviations were calculated and Shapiro-Wilk-W-tests for testing of
normality was conducted. As the data was non-normally distributed, a
Kruskal-Wallis/Wilcoxon test, followed by pairwise comparison with
Wilcoxon method, was carried out.