Cause | Number (%) of eyes with a visual acuity of 20/40 or worse | Number (%) of children with a visual acuity of 20/40 or worse in one or both eyes† | Prevalence rate of a visual acuity of 20/40 or worse in one or both eyes in the population† | |
---|---|---|---|---|
Right eye | Left eye | |||
*Standardised for age and grade level | ||||
†These figures refer to one or both eyes, thus their totals outnumber total causes. | ||||
Refractive error | 269 (85.4) | 262 (85.1) | 343 (87.3) | 6.13 |
Amblyopia | 27 (8.6) | 34 (11.0) | 52 (13.2) | 0.91 |
Corneal opacity | 3 (1.0) | 1 (0.3) | 3 (0.8) | 0.09 |
Cataract | 2 (0.6) | – | 2 (0.5) | 0.02 |
Retinal condition | 2 (0.6) | 1 (0.3) | 2 (0.5) | 0.04 |
Other | 6 (1.9) | 6 (1.9) | 9 (2.3) | 0.17 |
Undefined | 6 (1.9) | 4 (1.3) | 8 (2.0) | 0.30 |
Total | 315 (100) | 308 (100) | 393 (100) | 7.24 |