Table 1.
Demographic and cognitive measures
| DD
|
TD
|
t | p | |||
|---|---|---|---|---|---|---|
| M | SD | M | SD | |||
| Age (years) | 8.34 | 0.65 | 8.44 | 0.57 | −0.51 | .614 |
| IQ – WASI | ||||||
| Verbal | 106.9 | 12.40 | 109.2 | 13.46 | −0.52 | .605 |
| Performance | 109.3 | 16.36 | 111.8 | 12.45 | −0.52 | .606 |
| Full scale | 108.6 | 11.84 | 111.8 | 10.42 | −0.86 | .399 |
| Achievement – WIAT-II | ||||||
| Word Reading | 106.3 | 9.60 | 111.5 | 11.03 | −1.49 | .146 |
| Reading comprehension | 105.9 | 8.16 | 110.0 | 9.73 | −1.34 | .191 |
| Numerical operations | 84.6 | 3.69 | 115.8 | 3.55 | −25.74 | <.001 |
| Mathematical reasoning | 101.3 | 13.80 | 114.3 | 12.47 | −2.95 | .006 |
| Working Memory – WMTB-C | ||||||
| Digit recall1 | 105.3 | 17.68 | 106.3 | 12.62 | −0.19 | .851 |
| Block recall1 | 91.0 | 11.74 | 101.2 | 9.76 | −2.80 | .008 |
| Counting recall | 85.8 | 20.42 | 94.2 | 20.62 | −1.22 | .231 |
| Backward digit recall | 94.5 | 18.92 | 101.5 | 13.87 | −1.27 | .212 |
1
One participant in the DD group was excluded because their raw score was too low to be standardized. DD = Developmental Dyscalculia, TD = Typically Developing, WASI = Wechsler Abbreviated Scales of Intelligence, WIAT-II = Wechsler Individual Achievement Test –Second Edition, WMTB-C = Working Memory Test Battery for Children.