Table 4.
Prevalence rate of visual impairment in three examination sites
| Level of visual impairment | n* | Home | Village | Health center | P value† |
|---|---|---|---|---|---|
| Blindness (PDVA < 3/60) | 74 (1.6%) | 12/42 (28.6%) | 35/1473 (2.4%) | 27/3182 (0.8%) | |
| Severe visual impairment (3/60 ≤ PDVA < 6/60) | 34 (0.7%) | 2/42 (4.8%) | 12/1473 (0.8%) | 20/3182 (0.6%) | |
| Moderate visual impairment (6/60 ≤ PDVA < 6/18) | 354 (7.5%) | 1/42 (2.4%) | 135/1473 (9.2%) | 218/3182 (6.9%) | |
| Mild visual impairment (6/18 ≤ PDVA < 6/12) | 772 (16.4%) | 3/42 (7.1%) | 314/1473 (21.3%) | 455/3182 (14.3%) | |
| No visual impairment (PDVA ≥ 6/12) | 3463 (73.7%) | 24/42 (57.1%) | 977/1473 (66.3%) | 2462/3182 (77.4%) | |
| Total‡ | 4697 | 42/4697 (0.9%) | 1473/4697 (31.4%) | 3182/4697 (67.7%) | < 0.001 |
*“n” refers to the total numbers of different degrees of visual impairment from the three examination sites
†Kruskal Wallis test
‡PDVA was collected from 4697 persons
PDVA= presenting distance visual acuity