Table 1.
Diagnostic performance of graft assessment methods.
| Echo 1 | Echo 2 | Palpator 1 | Palpator 2 | |
|---|---|---|---|---|
| sensitivity | 1 (CI 0.61–1) |
0.83 (CI 0.44−0.97) |
0.33 (CI 0.01–0.7) |
0.5 (CI 0.19–0.81) |
| specificity | 1 (CI 0.61–1) |
1 (CI 0.61–1) |
0.17 (CI 0.03–0.56) |
0.83 (CI 0.44–0.97) |
| PPV | 1 (CI 0.61–1) |
1 (CI 0.57–1) |
0.28 (CI 0.08–0.64) |
0.75 (CI 0.3–0.95) |
| NPV | 1 (CI 0.61–1) |
0.86 (CI 0.49–0.97) |
0.2 (CI 0.04–0.62) |
0.625 (CI 0.3–0.86) |
| LR+ | ∞ (CI ∞-∞) |
∞ (CI ∞-∞) |
0.4 (CI 0.22–0.72) |
3 (CI 1.44–6.24) |
| LR− | 0 (CI 0–0.64) |
0.17 (CI 0.03–0.92) |
4 (CI 0.05–0.53) |
0.6 (CI 0.19–1.86) |
| overall accuracy | 1 (CI 0.76–1) |
0.92 (CI 0.65–0.98) |
0.27 (CI 0.1–0.57) |
0.67 (CI 0.39–0.86) |
| true positive | 6 | 5 | 2 | 3 |
| true negative | 6 | 6 | 1 | 5 |
| false positive | 0 | 0 | 5 | 1 |
| false negative | 0 | 1 | 4 | 3 |
Summary statistics for two independent investigators using echocardiography (Echo 1, 2) and two investigators performing graft palpation (Palpator 1, 2). Metrics are calculated against visual assessment of heartbeat cessation. An LR+ of ∞ indicates no false-positive results; an LR− of 0 indicates no false-negative results. PPV, positive predictive value; NPV, negative predictive value; LR +, positive likelihood ratio; LR−, negative likelihood ratio; CI, Confidence Interval; N, 12 mice.