Statistical analysis
primary disease
All data were reported as estimates of arithmetic mean and standard deviation except from ordinal scaled variables and those who violated normal distribution. For these we used the median and interquartile range (IQR). Fisher’s exact test was applied to explore the differences in age and primary disease between the groups. Kruskal–Wallis-Test tested the differences between the groups for the 3 baseline questions and the one-way analysis of variance for the rest of the baseline variables. The effects of the three groups (NMES, NMES + VR, control group) over time (t0 – t1) on the main endpoints was determined by a two-way repeated measures analysis of variance. The main effects of group and time were only reported if there was no significant interaction. If the interaction was significant, the one-way repeated measures analysis of variance in combination with post-hoc-Tests (Tukey-HSD) was used for each simple main effect. All requirements of the statistical tests were considered (e.g., homogeneity of variance by the Levene’s Test). The Mann–Whitney U-test was applied to test whether the intensity and the results of VAS differed between the NMES and NMES + VR groups. If the distributions of the two groups differ according to the Kolmogorov–Smirnov test, the test cannot make a statement about the difference of the medians, but of the average ranks.Statistical analysis was performed using the IBM SPSS Statistics version 28.0. A value of 