Reduced optimality. Number (%) of subjects with particular background factor
| DAMP (n = 62) | Comparison (n = 51) | Odds ratio (CI) | p value | |
|---|---|---|---|---|
| Social factors | ||||
| Ethnicity—immigrant | 6 (10) | 5 (10) | 1.0 (0.2 to 4.4) | 0.767 |
| Family structure—divorced | 19 (31) | 8 (16) | 2.4 (0.9 to 6.9) | 0.102 |
| Social class | ||||
| I | 4 (7) | 9 (18) | ||
| II | 12 (19) | 22 (43) | ||
| III | 46 (74) | 20 (39) | 4.5 (1.9 to 10.7) | < 0.001 |
| Mean (SD) | 2.7 (0.6) | 2.2 (0.7) | < 0.0001 | |
| Familial reduced optimality factors2-150 | ||||
| Speech/language retardation | 8 (13) | 1 (2) | 7.7 (0.9 to 348.0) | 0.037 |
| Learning disorder | 23 (38) | 9 (18) | 2.9 (1.1 to 8.0) | 0.029 |
| Motor clumsiness | 20 (33) | 6 (12) | 3.8 (1.3 to 12.4) | 0.014 |
| Left handedness | 16 (27) | 15 (29) | 0.9 (0.4 to 2.2) | 0.913 |
| Mental retardation or epilepsy | 5 (8) | 1 (2) | 4.5 (0.5 to 215.3) | 0.217 |
| Tics | 6 (10) | 8 (16) | 0.6 (0.2 to 2.1) | 0.540 |
| Attention deficit | 10 (17) | 3 (6) | 3.2 (0.8 to 19.0) | 0.137 |
| Presence of one or more reduced optimality familial factors | 49 (80) | 3l (61) | 2.6 (1.1 to 6.7) | 0.038 |
↵2-150 Two boys with DAMP were either living with foster parents or were adopted, and information about their family background was not obtained except one of the boys had a mother and brother with epilepsy.