Table 2.
Diagnostic accuracy of CAD-score with a cut-off of >20 according to a reference of (A) anatomically obstructive stenosis diagnosed with core lab QCA and (B) haemodynamically obstructive stenosis diagnosed with invasive FFR as reference
| CAD-score Version 2 | CAD-score Version 3 | |
| A. Anatomically obstructive stenosis | ||
| Number of patients | 1450 | 1437 |
| True positive | 100 | 119 |
| False positive | 720 | 606 |
| True negative | 577 | 683 |
| False negative | 53 | 29 |
| Accuracy analysis | ||
| Sensitivity | 65.4 (95% CI 57.3 to 72.9) | 80.4 (95% CI 73.1 to 86.5) |
| Specificity | 44.5 (95% CI 41.8 to 47.2) | 53.0 (95% CI 50.2 to 55.7) |
| PPV | 12.2 (95% CI 10.0 to 14.6) | 16.4 (95% CI 13.8 to 19.3) |
| NPV | 91.6 (95% CI 89.1 to 93.6) | 95.9 (95% CI 94.2 to 97.3) |
| PLR | 1.18 (95% CI 1.04 to 1.33) | 1.71 (95% CI 1.56 to 1.88) |
| NLR | 0.78 (95% CI 0.62 to 0.98) | 0.37 (95% CI 0.27 to 0.51) |
| AUC | 58.1 (95% CI 53.6 to 62.6) | 72.4 (95% CI 68.0 to 76.8) |
| B. Haemodynamically obstructive stenosis | ||
| Number of patients | 1450 | 1437 |
| True positive | 92 | 113 |
| False positive | 728 | 612 |
| True negative | 577 | 685 |
| False negative | 53 | 27 |
| Accuracy analysis | ||
| Sensitivity | 63.4 (95% CI 55.1 to 71.3) | 80.7 (95% CI 73.2 to 86.9) |
| Specificity | 44.2 (95% CI 41.5 to 47.0) | 52.8 (95% CI 50.0 to 55.6) |
| PPV | 11.2 (95% CI 9.1 to 13.6) | 15.6 (95% CI 13.0 to 18.4) |
| NPV | 91.6 (95% CI 89.1 to 93.6) | 96.2 (95% CI 94.5 to 97.5) |
| PLR | 1.14 (95% CI 1.00 to 1.30) | 1.71 (95% CI 1.56 to 1.89) |
| NLR | 0.83 (95% CI 0.66 to 1.03) | 0.36 (95% CI 0.25 to 0.50) |
| AUC | 56.8 (95% CI 51.8 to 61.7) | 71.3 (95% CI 66.8 to 75.8) |
AUC, area under the curve; FFR, fractional flow reserve; NLR, negative likelihood ratio; NPV, negative predictive value; PLR, positive likelihood ratio; PPV, positive predictive value; QCA, quantitative coronary angiography.