Table 4.
Signal Recovery and Precision Testing
| Input concentration (IU/mL) | Measured concentration (mean IU/mL) | Deviation Cmeasured-Cinput (log) | Variance analysis
|
||
|---|---|---|---|---|---|
| CV 18 replicates (%) | Intra-assay CV 6 replicates/run (%) | Inter-assay CV 3 runs (%) | |||
| 6.36E+02 | 1.52E+03 | 0.29 | 40.42 | 41.62 | 0.00* |
| 6.36E+03 | 5.89E+03 | −0.13 | 22.97 | 23.95 | 0.00* |
| 6.36E+04 | 4.62E+04 | −0.23 | 22.88 | 22.61 | 4.21 |
| 6.36E+05 | 4.00E+05 | −0.29 | 26.00 | 16.40 | 24.02 |
| 6.36E+06 | 4.40E+06 | −0.25 | 21.95 | 17.42 | 15.89 |
| 6.36E+07 | 4.52E+07 | −0.24 | 16.45 | 7.14 | 17.64 |
| 6.36E+08 | 3.80E+08 | −0.32 | 25.65 | 12.21 | 26.85 |
| 6.36E+09 | 2.78E+09 | −0.45 | 31.11 | 31.75 | 0.00* |
| 6.36E+10 | 3.00E+10 | −0.42 | 38.34 | 16.64 | 41.11 |
*
Zero set by the software tool.
A dilution series of a parvovirus B19 DNA-positive single donation in K3-EDTA plasma was extracted using the TNAI Kit on the COBAS AmpliPrep instrument in six replicates per run and a total of three runs at 3 days and analyzed with the LightCycler Parvovirus B19 Quantification Kit. The results were taken to determine the deviation between measured and input concentration. The overall CV (overall precision), the intra-assay CV (precision within a single run), and the inter-assay CV (precision run-to-run) were calculated as described.13