Table 3.

Comparison between RD-Only and RD+MD behavioral performance on cognitive, academic, and fMRI tasks

	RD-Only (N = 30)		RD+MD (N = 37)		Group Differences		Effect size
	M	(SD)	M	(SD)	t	p	d
Age	11.43	0.70	11.36	0.81	0.37	.713	0.09
Grade	5.50	0.63	5.43	0.77	0.39	.699	0.10
Sex (1=M, 2=F)	1.40	0.50	1.54	0.51	−1.14	.259	−0.28
Socioeconomic Status1	56.94	8.04	51.54	11.89	2.04	.045 *	0.52
Nonverbal Cognition2	107.67	10.87	102.70	11.01	1.85	.069	0.45
Reading and Related Skills
Phonological Awareness3	8.28	2.43	7.73	2.85	0.82	.414	0.20
Word Reading Efficiency4	83.97	8.27	78.56	10.07	2.35	.022 *	0.58
Basic Reading Skills Cluster5	82.70	9.90	79.75	9.86	1.21	.232	0.30
Mathematics
Math Facts Fluency Composite6	97.77	11.70	76.51	8.70	8.52	<.001 ***	2.09
Math Calculation Skills Cluster7	97.45	8.83	76.12	8.82	9.88	<.001 ***	2.44
Executive Function
Processing Speed8	97.17	12.21	87.11	13.11	3.17	.002 **	0.74
Auditory Working Memory Index8	93.62	14.23	84.57	10.34	2.99	.004 **	2.58
Visuospatial Working Memory Span9	6.29	1.23	5.44	1.34	2.23	.030 *	0.65
Visuospatial Working Memory Errors9	11.33	6.41	17.07	7.61	−2.78	.008 **	−0.81
fMRI tasks
Word Reading Task Accuracy	83.22	16.75	77.50	19.63	0.99	.330	0.31
Word Reading Response Time (sec)	1.86	0.28	1.80	0.32	0.63	.536	0.20
VSWM Task Accuracy	82.14	14.20	71.88	23.39	1.75	.088	0.52
VSWM Response Time (sec)	0.91	0.15	0.94	0.17	−0.72	.477	−0.22

Note.

¹Barratt Simplified Measure of Social Status (BSMSS)

²Kaufman Brief Intelligence Test (KBIT-2)

³Comprehensive Test of Phonological Processing (CTOPP-2) Elision subtest

⁴Test of Word Reading Efficiency (TOWRE-2)

⁵Woodcock Reading Mastery Tests (WRMT-III)

⁶Wechsler Individual Achievement Test (WIAT-III)

⁷Woodcock Johnson Test of Achievement (WJ-IV)

⁸Wechsler Intelligence Scale for Children (WISC-IV)

⁹Cambridge Neuropsychological Test Automated Battery (CANTAB). VSWM = Visuospatial Working Memory fMRI task.