Table 1.
Demographic and defining characteristics of the 44 dyslexics and 40 controls
| Characteristics | Dyslexics |
Controls |
Comparison |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean | SD | z-score | % impaired | Mean | SD | Value | p | ||
| Age | years | 27.7 | 10.6 | 0.2 | 9.1 | 25.5 | 10.5 | F = 0.9 | ns |
| Sex | male:female | 15:29 | — | — | — | 8:32 | — | χ2 = 1.4 | ns |
| Education | university:secondary | 33:11 | — | — | — | 31:09 | — | χ2 = 0.0 | ns |
| Performance IQ | scaled score | 107 | 12.1 | 0.1 | 0 | 108.8 | 13.8 | F = 0.4 | ns |
| Vocabulary | scaled score | 10.6 | 2.3 | 0.1 | 4.5 | 10.7 | 2.4 | F = 0.1 | ns |
| Similarities | scaled score | 12.8 | 2.7 | −0.3 | 0 | 11.9 | 3 | F = 2.1 | ns |
| Spelling | |||||||||
| Words | % errors | 23.3 | 11.7 | 4.8 | 77.2 | 8.1 | 3.1 | F = 61.2 | <.001 |
| Nonwords | % errors | 25.5 | 17 | 2.3 | 47.7 | 9.7 | 6.8 | F = 30 | <.001 |
| Reading | |||||||||
| Words | RT | 661 | 231 | 2.1 | 36.3 | 526 | 63 | F = 12.7 | .001 |
| Words | % errors | 5.9 | 3.4 | 3.3 | 65.9 | 2.2 | 1.1 | F = 42.1 | <.001 |
| Nonwords | RT | 1048 | 672 | 3.4 | 40.9 | 658 | 114 | F = 13.1 | <.001 |
| Nonwords | % errors | 27.8 | 13.2 | 5.6 | 86.4 | 7.2 | 3.7 | F = 90.4 | <.001 |
| Reading text | |||||||||
| Speed | ms | 243 | 100 | 1.8 | 29.5 | 179 | 36 | F = 14.6 | <.001 |
| Accuracy (/466 words) | N errors | 12.9 | 11.6 | 2.5 | 38.6 | 3.6 | 3.7 | F = 23.2 | <.001 |
| Comprehetion (/9 questions) | N errors | 4.7 | 2.1 | 0.6 | 11.4 | 3.6 | 1.9 | F = 2.1 | .01 |
Note: For text comprehension: 43 dyslexics and 38 controls; for text speed and accuracy: 40 dyslexics and 40 controls. Performance 2 standard deviations below the control mean is categorized as “impaired”. The sign of the z-scores for the scaled scores have been changed so that positive z-scores reflect worse performance matching the sign across errors and RT scores. RT = reaction time in ms.