Prevalence of infection, sensitivity, positive predictive value (PPV), negative predictive value (NPV) and Cohen’s kappa index (Kappa) (real-time PCR was taken as the reference standard)
| Method | Overall prevalencea | Sensitivityb | PPVb | NPVb | Kappac |
|---|---|---|---|---|---|
| Microscopy | 14/77 (18%) | 30.4 (17.1–43.7) | 100 (100) | 49.2 (38.0–60.4) | 0.26 (0.16–0.36) |
| CATT | 17/77 (22%) | 37.0 (23.0–50.9) | 100 (100) | 51.6 (40.5–62.8) | 0.09 (0.02–0.15) |
| Real-time PCR | 46/77 (60%) |
Comparison of microscopy and real-time PCR using McNemar’s chi-squared test
| Real-time PCR | Microscopy | Total | |
|---|---|---|---|
| Positive | Negative | ||
| Positive | 14 | 32 | 46 |
| Negative | 0 | 31 | 31 |
| Total | 14 | 63 | 77 |
Comparison of CATT and real-time PCR using McNemar’s chi-squared test
| Real-time PCR | CATT | Total | |
|---|---|---|---|
| Positive | Negative | ||
| Positive | 12 | 34 | 46 |
| Negative | 5 | 26 | 31 |
| Total | 17 | 60 | 77 |