Table 2.

Internal Consistency Reliability Metrics for the GACS

Subtest	Statistic	Age 6–17 n = 73	Age 18+ n = 30	Overall n = 103
Working Memory	M	14.9	16.5	15.2
	SD	4.3	17.0	4.2
	α	0.80	0.76	0.80
	SEM	1.9	1.8	1.9
Visual Processing	M	22.9	28.7	24.3
	SD	7.7	5.1	7.6
	α	0.94	0.88	0.94
	SEM	1.9	1.8	1.9
Auditory Processing	M	40.4	40.8	40.5
	SD	8.5	8.8	8.6
	α	0.92	0.93	0.92
	SEM	2.4	2.3	2.4
Logic & Reasoning	M	9.9	12.5	10.5
	SD	3.4	2.2	3.4
	α	0.82	0.60	0.81
	SEM	1.4	1.4	1.5
Processing Speed	M	25.5	32.4	27.0
	SD	6.9	3.6	7.0
	α	0.94	0.87	0.94
	SEM	1.7	1.3	1.7
Word Attack	M	13.7	18.7	14.9
	SD	6.0	3.9	5.9
	α	0.91	0.86	0.92
	SEM	1.8	1.5	1.7

Abbreviations: M, mean; SD, standard deviation; a, coefficient alpha; SEM, standard error of the mean.