| Cause | Blindness (VA<3/60) | Severe visual impairment (VA<6/60 to 3/60) | Visual impairment (VA<6/18 to 6/60) |
| n = 24 (%) | n = 7 (%) | n = 67 (%) | |
| Refractive error | 0 | 0 | 15 (22) |
| Cataract | 5 (21) | 3 (43) | 32 (48) |
| Surgery related | 1 (4) | 0 | 1 (2) |
| Uncorrected aphakia | 1 (4) | 0 | 0 |
| Corneal scar | 0 | 1 (14) | 0 |
| Phthisis/no globe | 1 (4) | 0 | 0 |
| Onchocerciasis | 4 (17) | 0 | 4 (6) |
| Posterior segment diseases | 7 (29) | 2 (29) | 9 (13) |
| Optic atrophy | 5 (21) | 1 (14) | 6 (9) |
| Avoidable* | 12 (50) | 4 (57) | 52 (78) |
*Cataract (corrected and uncorrected), refractive error, onchocerciasis, corneal scar and phthisis/no globe.