Table 4.
Mean Mathematics Achievement, IQ, and Cognition Performance
| Group |
|||
|---|---|---|---|
| MLD | LA | TA | |
| Mathematics achievement | |||
| First grade | 18 | 23 | 46 |
| Second grade | 8 | 22 | 63 |
| Third grade | 7 | 24 | 62 |
| IQ | 88 | 95 | 106 |
| Cognition | |||
| d′ | −1.02 | −0.41 | 0.50 |
| Central Executive | −0.71 | −0.30 | 0.44 |
| Phonological Loop | −0.65 | −0.25 | 0.36 |
| Visuospatial Sketch Pad | −0.53 | −0.19 | 0.30 |
| Correct Retrieval | −0.47 | −0.36 | 0.44 |
| Counting Error | −0.70 | −0.18 | 0.26 |
| Number Line | 0.85 | 0.45 | −0.58 |
Note: Mathematics achievement scores are national (U.S.) percentile ranks, and IQ values are standardized scores from the test manual with M = 100, SD = 15. Cognition values are z scores with M = 0, SD = 1. High Number Line scores = inaccurate placement.