Table 3.
Diagnostic ability for AD/NL by SVMst and SVMcog in several cohorts.
| SVMst (0.5) | SVMcog (0.5) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Database | NA-ADNI | AIBL | JADNI | MIRIAD | OASIS | NA-ADNI | AIBL | JADNI | MIRIAD | OASIS |
| AD/NL | 180/272 | 72/447 | 158/165 | 46/23 | 30/98 | 180/272 | 72/447 | 158/165 | 46/23 | 30/98 |
| AUC (%) | 0.9563 | 0.9535 | 0.9461 | 0.9934 | 0.9371 | 0.9908 | 0.9789 | 0.9930 | 1.0000 | 0.9871 |
| Accuracy (%) | 88.9 | 89.2 | 88.0 | 94.2 | 90.6 | 93.8 | 92.5 | 95.3 | 100.0 | 93.0 |
| Sensitivity (%) | 87.2 | 94.4 | 85.1 | 97.8 | 96.7 | 93.3 | 93.1 | 95.3 | 100.0 | 93.3 |
| Specificity (%) | 90.1 | 88.4 | 90.8 | 87.0 | 88.8 | 94.1 | 92.4 | 95.4 | 100.0 | 92.9 |
| PPV (%) | 85.3 | 56.7 | 90.0 | 93.8 | 72.5 | 91.3 | 66.3 | 95.3 | 100.0 | 80.0 |
| NPV (%) | 91.4 | 99.0 | 86.3 | 95.2 | 98.9 | 95.5 | 98.8 | 95.4 | 100.0 | 97.8 |
| F1 (%) | 86.3 | 70.8 | 87.5 | 95.7 | 82.9 | 92.3 | 77.5 | 95.3 | 100.0 | 86.2 |
| MCC (%) | 77.0 | 67.9 | 76.1 | 86.9 | 78.1 | 87.1 | 74.6 | 90.7 | 100.0 | 81.9 |
The numbers in parentheses indicate the cutoff value.
AD, Alzheimer's disease; NL, Normal subjects; ADNI, Alzheimer's disease neuroimaging Initiative; NA-ADNI, North American ADNI; AIBL, Australian Imaging, Biomarker & Lifestyle Flagship Study of Aging; JADNI, Japanese ADNI; MIRIAD, Minimal Interval Resonance Imaging in AD; OASIS, Open Access Series of Imaging Studies. PPV, positive predictive value (=precision); NPV, negative predictive rate; AUC, area under the curve; MCC, Matthews correlation coefficient.