Table 2. Frequency distributions of ocular risk factors in preschool children with and without inter-ocular visual acuity difference of two or more lines in the Multi-Ethnic Pediatric Eye Disease Study and the Baltimore Pediatric Eye Disease Study.
| Variable | With IOD (N=242) |
Without IOD (N=5455) |
P value** |
|---|---|---|---|
| n (%)* | n (%)* | ||
| Strabismus | ≤0.03† | ||
| No horizontal strabismus | 210 (3.8) | 5320 (96.2) | |
| Esotropia | 25 (27.5) | 66 (72.5) | |
| Exotropia | 7 (9.2) | 69 (90.8) | |
| SE anisometropia | <0.0001 | ||
| <0.50 D | 140 (3.1) | 4419 (96.9) | |
| 0.50 to <1.00 D | 52 (5.7) | 869 (94.3) | |
| 1.00 to <2.00 D | 25 (14.3) | 150 (85.7) | |
| ≥2.00 D | 25 (59.5) | 17 (40.5) | |
| J0 anisometropia | <0.0001 | ||
| <0.25 D | 170 (3.5) | 4709 (96.5) | |
| 0.25 to <0.50 D | 44 (6.6) | 620 (93.4) | |
| 0.50 to <1.00 D | 22 (16.5) | 111 (83.5) | |
| ≥1.00 D | 6 (28.6) | 15 (71.4) | |
| J45 anisometropia | <0.0001 | ||
| <0.25 D | 159 (3.4) | 4560 (96.6) | |
| 0.25 to <0.50 D | 46 (6.8) | 632 (93.2) | |
| 0.50 to <1.00 D | 27 (10.5) | 230 (89.5) | |
| ≥1.00 D | 10 (23.3) | 33 (76.7) |
IOD: inter-ocular visual acuity difference of 2 or more lines with visual acuity 20/32 or worse in the worse eye. SE: spherical equivalent. D: diopters. J0: J0 (Cartesian) power vector component of astigmatism. J45: J45 (oblique) power vector component of astigmatism.
*
Percentage of participants from both study centers with stated level of risk factor
**
Chi square or fisher exact where applicable
†
P value for comparison of esotropia vs. no horizontal strabismus: <0.0001; esotropia vs. exotropia: 0.003; exotropia vs. no horizontal strabismus: 0.03.