TABLE VII. Correlation Coefficients of the SQI Histogram Pairs.

Signal	Skewness	Kurtosis	Entropy	Zero-crossing	Upper	Lower
				rate	envelope	envelope
EEG 1	0.94	0.86	0.89	0.88	0.94	0.99
EEG 2	1.00	0.88	0.68	0.87	0.99	0.98
ECG	0.65	0.43	0.16	0.31	0.92	0.97
Resp	0.72	0.37	0.38	0.14	0.64	0.50