Table 2 Comparison of demographic details of the VPT and term groups.
| VPT cases | Term controls | |
|---|---|---|
| Parental social class | ||
| I | 20 | 23 |
| II | 43 | 20 |
| III | 50 | 21 |
| IV | 21 | 6 |
| V | 7 | 1 |
| Unclassified | 8 | 0* |
| Males/females | 78/75 | 41/30† |
| Handedness, | 83.6/15.0./1.4 | 92.8/4.3/2.9‡ |
| % right/left/mixed | ||
| Age at assessment in | 17.9 (0.67) | 18.5 (1.28)¶ |
| years, mean (SD) | ||
| Full scale IQ, | 107.0 (15.3) | 116.4 (17.8)§ |
| mean (SD) |
*For statistical comparison, social class was collapsed into two groups, higher (I and II) and lower (III–V and unclassified). χ2 (1,1) = 5.74; p = 0.017; †χ2 (1,1) = 0.892; p = 0.389; ‡χ2 (1,2) = 5.54; p = 0.063; ¶F = 16.17; df = 1,203; p<0.001; §F = 15.24; df = 1,204; p<0.001.