Table 1 Characteristics of current sample (DD, controls)

Age (yrs)

10.6 (1.6)

9.6 (1.5)

3.87

ns (> 0.05)

Gender (% female)

61%

55%

Χ²

ns

K-BIT IQ (ss)

91.0 (18.9)

99.8 (19.5)

1.8

ns

*WJIII Math Computation (ss)

84.2 (8.5)

95.6 (11.2)

12.3

.001

*WJIII Math Fact Fluency (ss)

71.6 (7.3)

92.2 (9.4)

53.9

.000

*Dyscalculia Screener Dot Enumeration (stanine) ¹

3.0 (1.5)

5.6 (1.7)

20.3

(df: 1, 32)

.000

*Dyscalculia Screener Number Comparison (stanine)

3.8 (1.5)

5.3 (1.9)

6.8

(df: 1, 32)

.01

Dyscalculia Screener Addition (stanine)

3.3 (1.3)

3.8 (1.6)

< 1

(df: 1, 32)

ns

Dyscalculia Screener Simple Reaction Time (stanine)

2.8 (1.2)

3.9 (1.4)

6.7

(df: 1, 32)

.01

WJIII Word Attack (ss)

99.8 (11.4)

106.2 (10.5)

2.7

ns

WJIII Letter-Word Identification (ss)

95.4 (13.0)

103.8 (11.1)

3.9

ns (> .05)

WJIII Reading Fluency (ss)

94.4 (16.4)

105.9 (15.4)

4.5

ns

Conners Parent DSM-IV Inattention (T-score)

60.9 (10.4)

58.6 (13.1)

< 1

ns

Conners Parent DSM-IV Hyperactivity/Impulsivity (T-score)

52.2 (12.4)

57.2 (12.6)

1.4

ns

Conners Teacher DSM-IV Inattention (T-score)

61.1 (6.2)

55.5 (6.4)

5.7

.02

Conners Teacher DSM-IV Hyperactivity/Impulsivity (T-score)

57.9 (14.3)

52.4 (9.8)

1.3

ns

RCMAS Total Anx T-score

48.0 (11.4)

42 (10.4)

< 1

ns

Working Memory

Cantab Spatial Span For (ss)

55 (0.8)

54 (1.0)

< 1

ns

Cantab Spatial Span Back (ss)

60 (0.7)

68 (.7)

2.1

> .1

Letter Span Forward (raw)

3.6 (1.1)

3.4 (.9)

< 1

ns

Letter Span Backward (raw)

1.6 (0.8)

1.6 (.8)

< 1

ns