Table 1 Comparative values of Septifast® (manual extraction) versus Septifast® (MagNa Pure® compact extraction)
From: Automation of Septifast®for molecular diagnosis of infection in septic patients
Blood culture vs. Septifast® (manual extraction) | Blood culture vs. Septifast® (MagNa Pure® compact extraction) | |
|---|---|---|
Sensitivity | 50 (27 to 72) | 80 (56 to 94) |
Specificity | 98.75 (93 to 99) | 95 (87 to 98) |
Positive predictive value | 90.9 (58 to 99) | 80 (56 to 94) |
Negative predictive value | 88.76 (80 to 94) | 95 (87 to 98) |
Prevalence | 20 | 20 |
Likelihood ratio positive test | 40 (5.43 to 294.5) | 15.99 (6 to 43.63) |
Likelihood ratio negative test | 0.506 (0.326 to 0.78) | 0.21 (0.087 to 0.5) |
Proportion agreement (strength of agreement) [1] | 0.89 (moderate) | 0.92 (substantial) |
Bias index | 0.09 | 0 |
Prevalence index | -0.69 | -0.6 |
Kappa (8) | 0.586 | 0.75 |
Extraction volume | 1,000 μl | 400 μl |
Time (extraction) | 4 to 3.5 hours | 25 to 30 minutes |