. 2016 Jun;208(6):548–555. doi: 10.1192/bjp.bp.114.145185

Table 1.

Group comparisons on age, gender, IQ, digit span, cognitive performance, ERP, EEG and actigraph measures

	F (d.f.) P	Cohen's d'	Cohen's d' (IQ controlled)
Mean age (s.d.)	1.45
	(2, 192)
	0.15

Male, n (%)	7.65
	(2, 192)
	0.02

Cognitive measures
IQ	22.35	−0.99^a**
	(2, 192)	−0.58^b*
	<0.01	−0.41^c
Digit span forward	7.40	−0.55^a**	−0.23^a
	(2, 192)	−0.36^b	−0.14^b
	<0.01	−0.19^c	−0.04^c
Digit span backward	13.01	−0.70^a**	−0.34^a*
	(2, 192)	−0.31^b	−0.08^b
	<0.01	−0.40^c	−0.21^c
RTV (CPT-OX)	10.86	0.68^a**	0.48^a**
	(2, 192)	0.55^b**	0.44^b*
	<0.01	−0.08^c	−0.09^c
RTV (fast task)	31.57	1.23^a**	0.83^a**
	(2, 190)	0.62^b**	0.44^b*
	<0.01	0.29^c	0.19^c
CE (CPT-OX)	10.28	0.69^a**	0.47^a**
	(2, 191)	0.28^b	0.17^b
	<0.01	0.24^c	0.19^c
OE (CPT-OX)	18.88	0.93^a**	0.63^a**
	(2, 191)	0.77^b**	0.59^b**
	<0.01	0.10^c	0.04^c

ERPs (CPT-OX)
CNV	6.52	0.54^a**	0.45^a**
	(2, 190)	0.42^b*	0.39^b
	<0.01	0.07^c	0.05^c
Cue P3	3.68	−0.37^a**	−0.39^a**
	(2, 190)	−0.27^b	−0.30^b
	0.03	−0.02^c	−0.05^c
No-Go P3	8.09	−0.61^a**	−0.57^a**
	(2, 188)	−0.22^b	−0.23^b
	<0.01	−0.27^c	−0.27^c

EEG frequency bands (CPT-OX)
Delta	4.84	0.44^a**	0.18^a
	(2, 189)	0.45^b*	0.35^b
	<0.01	−0.11^c	−0.18^c
Theta	3.89	0.35^a*	0.12^a
	(2, 189)	0.50^b*	0.36^b
	0.02	−0.14^c	−0.20^c
Alpha	3.28	0.39^a*	0.29^a
	(2, 189)	0.22^b	0.17^b
	0.04	0.14^c	0.13^c
Beta	2.36	0.33^a*	0.18^a
	(2, 189)	0.15^b	0.13^b
	0.10	0.08^c	0.04^c

Actigraph movement
Mean intensity	10.77	0.71^a**	0.59^a**
	(2, 169)	0.60^b**	0.53^b*
	<0.01	0.04^c	0.00^c
Mean count	13.77	0.87^a**	0.59^a**
	(2, 143)	0.80^b**	0.70^b*
	<0.01	0.01^c	−0.03^c

ERP, event-related potential; EEG, electroencephalogram; CPT-OX, continuous performance task; RTV, reaction time variability; CE, commission errors; OE, omission errors; CNV, continuous negative variation.

^a.

ADHD persisters v. controls.

^b.

ADHD persisters v. ADHD remitters.

^c.

ADHD remitters v. controls.

Cohen's effect sizes (d') are presented without and with IQ included as a covariate.

Significant group differences are indicated in bold.

P<0.05,

^**

P<0.01.