Causes of poor eyesight (visual acuity worse than 6/12)
| Unilateral poor eyesight | Bilateral poor eyesight* | Total* | |
|---|---|---|---|
| Causes | No (%)‡ | No (%)‡ | No (%) |
| *One student had bilateral myopia and optic atrophy and has been included under both conditions, but only once in the total. | |||
| †These individuals are also included under the appropriate refractive error, but only once in the total. | |||
| ‡Percentage of all students (n = 2511). | |||
| Refractive errors | |||
| myopia +/− astigmatism* | 24 (0.96) | 117 (4.66) | 141 (5.62) |
| hyperopia +/− astigmatism | 7 (0.28) | 3 (0.12) | 10 (0.40) |
| astigmatism only | 2 (0.08) | 1 (0.04) | 3 (0.12) |
| refractive error and amblyopia† | 3 (0.12) | 4 (0.16) | 7 (0.28) |
| Subtotal | 33 (1.31) | 121 (4.82) | 154 (6.13) |
| Anterior segment | |||
| corneal scar | 3 (0.12) | 0 (0.00) | 3 (0.12) |
| cataract | 1 (0.04) | 0 (0.00) | 1 (0.04) |
| aphakia and amblyopia | 0 (0.00) | 1 (0.04) | 1 (0.04) |
| Subtotal | 4 (0.16) | 1 (0.04) | 5 (0.20) |
| Posterior segment | |||
| optic atrophy* | 3 (0.12) | 4 (0.16) | 7 (0.28) |
| optic nerve coloboma | 1 (0.04) | 0 (0.00) | 1 (0.04) |
| retinopathy or maculopathy or macular scars | 6 (0.24) | 0 (0.00) | 6 (0.24) |
| Subtotal | 10 (0.40) | 4 (0.16) | 14 (0.56) |
| Others | |||
| strabismic amblyopia | 1 (0.04) | 0 (0.00) | 1 (0.04) |
| phthisis | 1 (0.04) | 0 (0.00) | 1 (0.04) |
| Subtotal | 2 (0.08) | 0 (0.00) | 2 (0.08) |
| Total | 49 (1.95) | 125 (4.98) | 174 (6.93) |