Fig. 1. (A ) Auditory evoked potential (AEP) index, (B ) Bispectral Index (BIS), and (C ) sevoflurane concentration at different observers’ assessments of alertness and sedation (Observer’s Assessment of Alertness/Sedation [OAA/S]) scores during sevoflurane-induced sedation. The values are either median (25th–75th, 10th–90th percentile interval) or individual.