TABLE 1. Group Differences in Power and Cordance.

Mean (s.d.) absolute and relative power and cordance values at all locations are shown comparing CON and MDD subjects (with t-statistics and uncorrected 2-tail p-values). Only at the Fpz location did cordance differ between controls and all depressed subjects after a Bonferroni correction was applied; no significant differences were found at other electrode sites in any of the three measures.

ABSOLUTE POWER
	Fpz	Fz	Cz	Pz	Oz	Fp1	Fp2
CON	19.88 (13.82)	29.51 (19.41)	35.26 (24.32)	36.35 (27.16)	27.74 (21.07)	20.28 (13.90)	20.47 (14.17)
MDD	24.95 (22.51)	38.66 (32.66)	46.90 (42.90)	49.68 (52.50)	40.07 (42.20)	27.54 (24.96)	27.77 (25.01)
t	−1.76; df 135a	−2.23; df 139a	−2.21; df 144a	−2.15; df 153a	−2.51; df 156a	−2.38; df 146a	−2.38; df 144a
p	0.080	0.027	0.029	0.033	0.013	0.018	0.019

RELATIVE POWER
	Fpz	Fz	Cz	Pz	Oz	Fp1	Fp2
CON	17.29 (6.54)	19.35 (6.66)	18.10 (6.74)	15.88 (6.65)	14.70 (6.22)	17.20 (6.28)	17.14 (6.49)
MDD	18.23 (8.74)	20.58 (8.60)	19.60 (8.50)	17.22 (8.28)	15.86 (7.92)	18.37 (8.51)	18.37 (8.52)
t	−0.66; df 166	−0.88; df 166	−1.09; df 166	−0.99; df 166	−0.90; df 166	−0.86; df 166	−0.89; df 166
p	0.508	0.382	0.277	0.322	0.371	0.394	0.374

CORDANCE
	Fpz	Fz	Cz	Pz	Oz	Fp1	Fp2
CON	−1.46 (1.44)	0.14 (1.43)	0.61 (1.18)	−1.19 (0.85)	−0.96 (1.55)	−0.88 (1.27)	−1.07 (1.35)
MDD	−0.78 (1.45)	0.11 (1.30)	0.21 (1.35)	−1.32 (1.06)	−1.02 (1.41)	−0.95 (1.29)	−1.02 (1.37)
t	−2.75; df 166	0.14; df 166	1.78; df 166	0.75; df 166	0.25; df 166	0.33; df 166	−0.25; df 166
p	0.0066 *	0.888	0.077	0.456	0.806	0.739	0.804

^at-test for equality of means performed for unequal variances based on significant Levene’s test finding