Table 2.

MEG data characteristics

Data characteristic	Madrid		Cambridge		Oxford	ANOVA
	Controls	MCI	Controls	MCI	MCI	Site	Group	Interaction
N	42	42	42	39	3	-	-	-
Bad channels	7.38	6.93	4.64	6.07	4.33	Sig∗	ns	ns
M move (mm)†	0.80	1.10	0.61	0.94	3.15	ns	Sig∗	ns
SD move (mm)†	0.18	0.30	0.06	0.24	3.04	ns	ns	ns
Position (mm)	10.5	12.0	10.0	12.9	13.9	ns	Sig∗	ns
Time of day (24h)	12.0	11.6	14.2	14.0	13.5	Sig∗	ns	ns
Data onset (s)	250	234	125	132	124	-	-	-
Data offset (s)	419	404	298	306	294	-	-	-
No. of epochs	38.2	39.7	39.8	37.8	33.0	ns	ns	Sig∗

Abbreviations: M, mean; MEG, magnetoencephalography; SD, standard deviation.

^∗P < .05.

^†Head motion excluded 12 participants for whom head motion could not be estimated.