Table 7. Cohen’s kappa coefficient (K) results for the comparison between protocols with the Real-Time PCR procedure as the only variable.
K values are shown including and excluding inhibited samples.
| Protocols | N | K value (95% CI) | Positive samples | Inhibited samples | N excluding inhibition | Discordant samples excluding inhibition | K value excluding inhibited samples (95% CI) |
|---|---|---|---|---|---|---|---|
| A-B | 123 | 0.79 (0.68–0.9) | 59 | 0 | 123 | 13a | 0.79 (0.68–0.9) |
| C-D | 62 | 0.44 (0.29–0.6) | 8 | 35 | 27 | 4 | 0.68 (0.41–0.96) |
| E-F | 25 | 0.84 (0.62–1) | 10 | 0 | 25 | 2 | 0.84 (0.62–1) |
| G-H | 64 | 0.92 (0.81–1) | 15 | 2 | 62 | 0 | 1 |
aNone of these samples were positive in all three replicates.
N: number of samples assessed in parallel by both protocols compared. Positive samples: number of samples with a positive result for both protocols. Inhibited samples: number of samples with an invalid result for the internal amplification control (IAC) in at least one of the two protocols compared. CI: confidence interval.