Test | ALL mean (n = 19) | Siblings mean (n =19) | Mean (SE) difference | Wilcoxon Z score | p Value |
---|---|---|---|---|---|

Arithmetic | 8.42 | 9.63 | −1.21 (0.65) | −1.89 | 0.02 |

Digit span | 7.68 | 9.42 | −1.74 (0.54) | −2.66 | 0.004 |

Coding | 8.79 | 10.63 | −1.84 (0.78) | −2.03 | 0.04 (two tailed) |

Speed of info | 48.50 | 55.44 | −6.94 (2.23) | −2.60 | 0.005 |