Table 4.

Comparison of estimated marginal means of delta impedance by electrode subset based on the linear mixed model, including basal (electrodes 3–6), middle (electrodes 10–13), and apical (electrodes 19–22) subsets.

Comparison	Estimate	SE	df	T-ratio	p-value
Basal–middle	652	76.5	4,479	8.528	< 0.0001
Basal–apical	1,509	76.5	4,479	19.721	< 0.0001
Middle–apical	857	76.5	4,479	11.201	< 0.0001

SE, standard error; df, degrees of freedom.