Table 5.
Accuracy of clinic level diagnosis compared with double or triple read reference slides. Values are number/number in group (percentage) unless stated otherwise
| Variables | North: new microscopy | East: established microscopy | Clinician in north* |
|---|---|---|---|
| False positive result | 39/193 (20.2)† | 329/1212 (27.1) | 412/413 (99.8) |
| False negative result | — | 47/451 (10.4) | 0/1 |
| Sensitivity, % (95% CI) | — | 89.6 (88.1 to 91.1) | 100 |
| Specificity, % (95% CI) | 79.8 (73.4 to 85.2) | 72.9 (70.7 to 75.0) | 0.2 (0 to 0.7) |
| Positive predictive value | — | 55.1 (52.7 to 57.5) | 0.2 (0 to 0.7) |
| Negative predictive value | — | 95.0 (93.9 to 96.0) | 100 |
*Against clinicians diagnosis based on signs and symptoms alone.
†New compared with established microscopy: Fisher’s exact, P=0.02.