Table 4.
Sensitivity/specificity analysis using CD4 count thresholds, WHO clinical status, TB status, presence of ocular symptoms, presence of visual impairment
| Factor | Number with HIV eye disease (n = 26) | Number without HIV eye disease | Sensitivity | Specificity | Positive predictive value | Number needed to screen* (95%CI) |
|---|---|---|---|---|---|---|
| (n = 123) | (95% CI) | (95% CI) | (95% CI) | |||
| WHO Clinical status | ||||||
| Stage 1/2 | 2 | 58 | 7.7 (1.3-26.6) | 52.8 (43.7-61.8) | 3.3 (0.6-12.5) | 30.3 (8-166.7) |
| Stage 3/4 | 24 | 65 | 92.3 (73.4-98.6) | 47.2 (38.2-56.3) | 27.0 (18.3-37.6) | 3.7 (2.9-5.5) |
| TB status | ||||||
| Past/current TB | 19 | 60 | 73.1 (52.0-87.6) | 51.2 (42.0-60.2) | 24.1 (15.4-35.2) | 4.1 (2.9-6.5) |
| CD4 count (cells/μL) | ||||||
| ≤ 50 | 7 | 6 | 27.0 (12.4-48.0) | 95.1 (89.2-98.0) | 53.8 (26.1-78.0) | 1.9 (1.3-3.8) |
| ≤ 100 | 13 | 23 | 50.0 (30.4-69.6) | 81.3 (73.1-87.5) | 36.1 (21.3-53.8) | 2.8 (1.9-4.7) |
| ≤ 150 | 18 | 41 | 69.2 (48.1-84.9) | 66.7 (57.5-74.8) | 30.5 (19.5-44.0) | 3.3 (2.3-5.1) |
| ≤ 200 | 20 | 64 | 76.9 (55.9-90.2) | 48.0 (38.9-57.1) | 23.9 (15.5-34.6) | 4.2 (2.9-6.5) |
| ≤ 250 | 22 | 89 | 84.6 (64.3-95.0) | 27.6 (20.1-36.6) | 19.8 (13.1-28.7) | 5.1 (3.5-7.6) |
| Ocular symptoms | ||||||
| Present | 2 | 9 | 7.7 (4.0-13.2) | 92.6 (86.1-96.3) | 18.1 (3.2-52.2) | 5.5 (1.9-31.2) |
| Vision status | ||||||
| Visual impairment | 5 | 7 | 20.0 (7.6-41.3) | 94.0 (87.6-97.3) | 41.7 (16.5-71.4) | 2.4 (1.4-6.0) |
*The number needed to screen (NNS) is the number of people that need to be screened to detect one new case of eye disease