Table 3.

Performance of groups with and without ADHD and COP on the neuropsychological battery

	Summary statistics for each group				Effect sizes for pairwise comparisons between groups
	Control M (SD)	ADHD only M (SD)	COP only M (SD)	COP+ADHD M (SD)	ADHD only vs. Control	COP only vs. Control	COP+ADHD vs. Control	COP only vs. ADHD only	COP+ADHD vs. ADHD only	COP+ADHD vs. COP only
Intelligence
Verbal IQ	112.5 (13.8)	100.1 (15.8)	93.9 (15.2)	94.6 (17.5)	0.84***	1.33***	1.19***	0.39	0.33	−0.04
Performance IQ	112.7 (16.8)	97.8 (17.0)	100.0 (12.2)	93.7 (19.7)	0.88***	0.78*	1.07***	0.13	0.23	0.35
Full Scale IQ	112.6 (13.7)	99.0 (16.1)	96.4 (10.9)	94.2 (13.8)	0.91***	1.21**	1.34***	0.17	0.31	0.17
Sentence Span
Correct Sets	6.0 (1.9)	4.2 (2.0)	2.7 (1.5)	3.5 (1.9)	0.95***	1.78***	1.32***	0.77*	0.39*	−0.44
Stop-signal Task
Stop-signal RT	273 (114)	419 (132)	466 (126)	421 (136)	1.19***	1.53***	1.22***	0.36	0.02	−0.34
Go Trial RT	679 (100)	717 (97)	736 (110)	745 (99)	0.39***	0.56*	0.66**	0.19	0.29	0.09
Go Trial RT SD	155 (57)	238 (61)	254 (59)	224 (61)	1.35***	1.73***	1.19***	0.26	−0.23	−0.50
Selective Attention
Proportion correct	.87 (.10)	.77 (.14)	.71 (.08)	.78 (.13)	0.79**	1.64***	0.82***	0.44	−0.07	−0.58
Response time	1104 (356)	1374 (351)	1317 (247)	1442 (452)	0.76**	0.62*	0.87***	−0.17	0.18	0.30
RT SD	482 (292)	804 (468)	985 (432)	1012 (596)	0.85**	1.39***	1.19***	0.40	0.39	0.06

Note: The means in the table are based on raw scores, but age-corrected scores were used in all statistical analyses and to calculate effect sizes (Cohen’s d). Positive effect sizes indicates that the group listed first is more impaired.

^*P < .05,

^**P < .01,

^***P < .001