| Child’s visual defect at 7 | Parental occupational social class | p Value χ2 trend | |||
| n = 6935 | I | II | III (NM) | III (M)/IV/V | |
| n = 1078 | n = 3117 | n = 1723 | n = 1017 | ||
| All manifest strabismus (n = 155) | 17 (1.6) | 68 (2.2) | 47 (2.7) | 23 (2.3) | 0.153 |
| Clinically significant convergent strabismus (n = 196) | 24 (2.2) | 81 (2.6) | 59 (3.4) | 32 (3.1) | 0.066 |
| Clinically significant divergent strabismus (n = 41) | 2 (0.2) | 20 (0.6) | 13 (0.8) | 6 (0.6) | 0.221 |
| Amblyopia (ever) (n = 239) | 27 (2.5) | 106 (3.4) | 69 (4.0) | 37 (3.6) | 0.089 |
| Impaired presenting vision in best eye (n = 36)* | 5 (0.5) | 20 (0.6) | 5 (0.3) | 6 (0.6) | 0.728 |
| Hypermetropia (n = 329) | 35 (3.2) | 144 (4.6) | 96 (5.6) | 54 (5.3) | 0.010 |
| hypermetropia, clinically significant convergence or amblyopia (n = 501) | 56 (5.2) | 231 (7.4) | 138 (8.0) | 76 (7.5) | 0.041 |
*Twenty children had missing data for this variable, so the denominators for the columns showing SC catgories I, II, II(NM) and III(IM)-V, respectively, are 1074, 3109, 1718 and 1014.