| Age Group | N | Mean | SD | Mínimum | Maximum |
| 7 - 11 | 140 | −2.9 | 21.1 | −66 | 62 |
| 12 - 14 | 116 | −6.2 | 23.5 | −72 | 48 |
| 15 - 17 | 69 | −8.3 | 21.2 | −74 | 40 |