Questioning the evidence for BCI-based communication in the complete locked-in state
In the following, the statistical analysis is described that was originally performed for the comment, but was replaced with a different analysis after the first review round of the comment. For each patient separately, the data of all sessions were used and a Wilcoxon's ranksum test was performed for each channel and each sample. The minimum p-value for Patient F was p=0.0026, for Patient G p>0.05, for Patient B p=0.0317, and for Patient W p=0.0109. Due to the large number of tests involved (20 channels with 93 samples equals 1860 tests), the results must be corrected for multiple comparisons. Using a Bonferroni correction with a significance level of α=0.05, the adjusted significance level is α / 1860 = 0.000027, showing that there is no significant difference in the hemodynamic response between "yes" and "no" questions for any of the 4 patients.