Table 1.

IQ, math, reading and multicomponent working memory measures in children with mathematical disabilities (MD) and typically developing (TD) children. Visuo-spatial working memory scores were significantly lower in children with MD, compared to TD children.

Measure	MD		TD
	M (Range)	SD	M (Range)	SD
Age (months)	98.78 (86–109)	6.97	97.84 (88–108)	6.26
WASI
Verbal	106.65 (78–128)	12.32	108.29 (80–138)	15.93
Performance	107.59 (77–140)	18.20	113.77 (86–145)	13.32
Full Scale	107.71 (83–130)	13.36	112.35 (94–127)	10.20
WIAT–II
Word Reading	108.47 (93–122)	9.23	112.06 (90–130)	9.65
Numerical Operations	85.71 (79–91)	3.50	118.29 (95–156)***	15.41
Mathematical Reasoning	102.47 (84–130)	14.82	115.00 (90–137)*	12.20
WMTB-C
Digit Recall	105.71 (77–144)	20.40	107.12 (75–144)	17.50
Counting Recall	86.94 (60–117)	18.63	87.35 (56–110)	17.03
Block Recall	91.00 (56–114)	14.62	102.18 (81–118)*	9.91
Backward Digit Recall	96.94 (72–131)	19.45	99.35 (81–135)	13.87

Note: WASI=Wechsler abbreviated scales of intelligence, WIAT-II=Wechsler individual achievement test—2nd ed., WMTB-C=Working memory test battery for children.

^*p<.05.

^***p<.001.