Table 2.
Reproducibility of PSA measurements with COIN- or Alexa-conjugated antibody reagents
| Detection method | Signal/background %CV (mean ± SD) | Spot-to-spot variation %CV (mean ± SD) | Accuracya %CV (mean ± SD) |
|---|---|---|---|
| Intra-assay variabilityb | |||
| PSA–COIN | 43% (13 ± 6) | 14% (111 ± 16) | 3% (0.91 ± 0.03) |
| PSA–Alexa | 45% (6 ± 3) | 11% (34 ± 4) | 2% (0.97 ± 0.02) |
| Inter-assay variabilityc | |||
| PSA–COIN | 54% (10 ± 5) | 10% (109 ± 11) | 4% (0.89 ± 0.04) |
| PSA–Alexa | 41% (5 ± 2) | 13% (33 ± 4) | 2% (0.97 ± 0.02) |
| Inter-lot variabilityd | |||
| PSA–COIN | 48% (9 ± 4) | 19% (100 ± 19) | 3% (0.89 ± 0.03) |
Fraction of correctly classified spots in the epithelium and stroma, i.e., (true positive pixels + true negative pixels)/total pixels.
Variability between individual glands on the same slide. Data include nine gland pairs measured in parallel for COIN and Alexa in one experiment. This data set is representative of individual experiments, four of which are summarized by the inter-lot variability below.
Variability between glands measured on different days using the same reagents. Data include a total of 13 gland pairs measured in parallel for COIN and Alexa in two experiments.
Variability between glands measured on different days using different reagents. Data include independent experiments from four different COIN.