TABLE 4.
Intra-assay variation | Inter-assay variation | |||||
---|---|---|---|---|---|---|
Cells per reaction | Cq, mean (SD)—Plate 1 | Cq, mean (SD)—Plate 2 | Cq, mean (SD)—Plate 3 | CV a (%) | Cq, mean (SD) | CV b (%) |
1.57 E7 | 17.88 (0.16) | 18.05 (0.32) | 17.59 (0.52) | 1.895 | 17.84 (0.23) | 1.313 |
1.57 E6 | 20.74 (0.29) | 21.36 (0.22) | 19.84 (0.13) | 1.032 | 20.65 (0.77) | 3.717 |
1.57 E5 | 23.96 (0.12) | 23.74 (0.12) | 22.89 (0.15) | 0.543 | 23.53 (0.57) | 2.405 |
1.57 E4 | 27.05 (0.15) | 27.22 (0.41) | 26.48 (0.45) | 1.258 | 26.92 (0.39) | 1.440 |
1.57 E3 | 30.30 (0.24) | 30.24 (0.20) | 29.97 (0.23) | 0.749 | 30.17 (0.17) | 0.575 |
1.57 E2 | 33.81 (0.33) | 33.70 (0.25) | 33.02 (0.10) | 0.679 | 33.51 (0.43) | 1.277 |
The intra-assay CV was calculated by generating the mean Cq and SD for replicates of each of the six standards within a given plate and then averaging the within-plate CVs for each standard across the three different plates that were run.
The inter-assay CV was calculated by determining the mean Cq value for all replicates of each of the six standards within a plate. The overall mean computed as the mean Cq per plate and SD computed as the SD of the mean Cq per plate were used to determine an inter-assay CV% for each standard.
CV, coefficient of variation; SD, standard deviation; Cq, cycle quantification number.