Fig. 5. Population statistics for the induced power over periods for the frequency bands 58–114 Hz, 114–228 Hz, and 228–457 Hz for the groups of anesthetics and opioids separately. There are significant differences in induced power of single sweeps accounting for the brainstem auditory-evoked potential (BAEP) wave V between periods for all kinds of anesthetics and opioids used for the frequency bands 57–114 Hz, 114–228 Hz, and 228–457 Hz. The pattern as expressed by the population statistics (median, upper and lower quartile [  box ], 1.5 times interquartile range [  dotted line ], and outliers [  crosses ]) resembles for the anesthetics and opioids used. There is a decrease in induced power and variability for the periods that account for general anesthesia and an increase towards the end of anesthesia again. Differences between drug groups consist in a differing variability at certain periods. Please note that group sizes are different as indicated in  table 1 .