Table 2.
Estimates (95% lower, upper confidence levels) of mean cut-off Cp values after amplification of a dilution of titrated virus in uniplex and multiplex real time RT-PCR for a test sensitivity of 97%a
| Mean Cut-off Cp value | |||
|---|---|---|---|
| Virus | Copy number | Uniplex RTPCR | Multiplex RTPCR |
| BRSV | 103 | 32.9 (32.1, 33.6) | 33.0 (32.2, 33.7) |
| 102 | 35.4 (34.5, 36.1) | 35.4 (34.6, 36.1) | |
| 10 | 37.7 (36.8, 38.5) | 37.7 (36.9, 38.5) | |
| BoHV-1 | 103 | 31.4 (31.0, 31.9) | 31.4 (31.0, 31.9) |
| 102 | 35.2 (34.8, 35.8) | 35.2 (34.8, 35.8) | |
| 10 | 37.1 (36.6, 37.6) | 37.1 (36.6, 37.6) | |
| BPI3 i | 103 | 31.7 (31.2, 32.4) | 32.5 (31.9, 33.1) |
| 102 | 34.4 (33.9, 35.1) | 35.2 (34.6, 35.8) | |
| 10 | 39.4 (39.0, 40.2) | 40.2 (39.7, 41.0) | |
| BPI3 ii | 103 | 32.4 (32.2, 32.8) | 32.8 (32.6, 33.1) |
| 102 | 34.7 (34.4, 35.0) | 35.1 (34.9, 35.4) | |
| 10 | 38.4 (38.2, 38.8) | 38.9 (38.7, 39.2) | |
a For each virus, a 10-fold dilution series is shown with the mean Cp values. The lowest level of detection is shown, as are the two 10-fold dilutions immediately prior to the lowest level of detection. Each dilution series was tested four times in triplicate. The estimates of the mean cut-off Cp value for a test sensitivity of 97% and corresponding 95% confidence intervals were obtained using a bootstrap sampling procedure (see text for detail).