Table 6.

Parameters of linear regression for different bicoherence estimates in association with graduated levels of anaesthesia.

(a) Bifrequency region	Coef (95% conf. interval)	z value	p-value	ρ	R2
δ_δ	1.217 (1.105 - 1.33)	21.27	< 0.001	0.462	0.152
δ_θ	0.985 (0.906 - 1.063)	24.61	< 0.001	0.509	0.168
δ_α	0.269 (0.227 - 0.311)	12.66	< 0.001	0.445	0.060
δ_β	0.066 (0.051 - 0.081)	8.67	< 0.001	0.356	0.036
θ_θ	0.403 (0.325 - 0.48)	10.21	< 0.001	0.426	0.044
θ_α	0.19 (0.145 - 0.236)	8.25	< 0.001	0.476	0.024
θ_β	0.007 (-0.01 - 0.024)	0.83	0.408	0.468	0.002
α_α	0.186 (0.115 - 0.258)	5.14	< 0.001	0.439	0.011
α_β	-0.002 (-0.024 - 0.019)	-0.21	0.831	0.499	0.002
β_β	-0.032 (-0.053 - -0.011)	-2.95	0.003	0.723	0.004
(b) Bifrequency region	Coef (95% conf. interval)	z value	p-value	ρ	R2
δ_δ	1.883 (1.728 - 2.038)	23.82	< 0.001	0.433	0.184
δ_θ	1.903 (1.758 - 2.048)	25.74	< 0.001	0.472	0.191
δ_α	0.786 (0.674 - 0.898)	13.74	< 0.001	0.396	0.072
δ_β	0.377 (0.304 - 0.449)	10.17	< 0.001	0.195	0.053
θ_θ	1.232 (1.069 - 1.394)	14.82	< 0.001	0.448	0.080
θ_α	0.582 (0.47 - 0.695)	10.18	< 0.001	0.502	0.036
θ_β	0.117 (0.05 - 0.184)	3.44	0.001	0.343	0.005
α_α	0.587 (0.432 - 0.742)	7.44	< 0.001	0.458	0.020
α_β	0.207 (0.128 - 0.287)	5.13	< 0.001	0.391	0.012
β_β	-0.059 (-0.133 - 0.015)	-1.56	0.119	0.656	0.008

(a) Average and (b) smoothed-peak bicoherence estimates. Linear regression performed using the univariate generalised linear mixed effects model where ρ is the intraclass correlation based on a random intercept model.