Table 5.

Summary of levels of anaesthesia, what EEG states they relate to and sample sizes.

Sedation level	Meaning	Including EEG states	Sample size
			Number of observations	Number of subjects
1	Awake	2, 3 & 4	169	40
2	Drowsy/very light anaesthesia	5	11	5
3	Light anaesthesia	6	14	4
4	Moderate anaesthesia	7	444	31
5	Deep moderate anaesthesia	8	999	40
6	Deep anaesthesia	9	159	24