Table 4.

Working memory performance for ADHD subtypes and normal controls

Measure
	ADHD-CT (n = 17)		ADHD-IA (n = 16)		NC (n = 18)
	M	SE	M	SE	M	SE	Post hoc comparisons with covariates
Arithmetic	11.65	0.58	11.75	0.60	13.39	0.56	ns
Digit Span	11.71	0.66	11.12	0.68	13.39	0.64	NC>ADHD-IA (p = .02)b
Letter-Number-Sequencing	11.65	0.69	11.31	0.71	14.33	0.67	NC>ADHD-CT, ADHD-IA (p = 0.03)
Spatial Span	11.59	1.02	11.00	0.42	11.94	0.53	ns
PASAT Averaged over ISIa	(n = 16)		(n = 14)		(n = 17)
Correct	31.66	2.17	31.64	2.33	38.81	2.11	ns
Omission Errors	15.33	1.97	15.59	2.10	8.22	1.91	NC<ADHD-CT (p = 0.008)
Longest Sequence	8.25	2.58	12.31	2.62	16.91	2.50	NC<ADHD-CT (p = 0.02)

Note. NC = normal control, ADHD-IA = inattentive type, ADHD-CT = combined type.

^aIn some cases on the PASAT there were missing data due to technical problems in the computer recording responding. This included missing data for one ADHD-CT participant, two ADHD-IA participants, and one NC participant for PASAT measures only.

^bExploratory analyses