TABLE 1.
Accuracy of pooling urine samples for the detection of genital C. trachomatis infection in asymptomatic women by LCRa
| Parameter | Result for pool size with indicated no. of samples
|
|
|---|---|---|
| 4 | 10 | |
| Total no. of urine samples | 568 | 520 |
| No. of positive specimens (%) | 48 (8.6) | 62 (11.9) |
| No. of pools | 142 | 52 |
| No. of presumptive-positive pools | 45 | 39 |
| Estimated population prevalence calculated from pooled data (95% CI) | 9.1 (6.5, 11.6) | 12.9 (8.8, 17.0) |
| No. of samples retested individually (%) | 180 (31.7) | 390 (75.0) |
| No. of positive pools (%) | 43 (30.3) | 38 (73.1) |
| Sensitivity of the pools (%) | 43/43 (100) | 37/38 (97.4) |
| Pooling algorithm sensitivity (%) | 48/48 (100) | 61/62 (98.4) |
| Specificity of the pools (%) | 97/99 (98.0) | 13/14 (92.9) |
| Pooling algorithm specificity (%) | 520/520 (100) | 458/458 (100) |
| Total no. of assays performed | 322 | 442 |
| No. of assays saved | 246 | 78 |
a
For the pooling algorithm, samples were first tested pooled and then presumptive-positive pools were retested individually.