Table 4.
Sensitivity, Specificity, Positive Predictive Value, Negative Predictive Value, and Accuracy at Various Cutoff Points of HCage and HCnorm for Predicting Aβ Positivity in Patients with Mild Cognitive Impairment
| Cutoff | Sensitivity | Specificity | Positive Predictive Value | Negative Predictive Value | Accuracy |
|---|---|---|---|---|---|
| HCage | |||||
| >-14.6 | 100 | 2.8 | 45.3 | 100.0 | 46.2 |
| >-14.1 | 98.3 | 2.8 | 44.9 | 66.7 | 45.4 |
| >-13.6 | 93.1 | 15.3 | 47.0 | 73.3 | 50.0 |
| >-13.1 | 89.7 | 31.9 | 51.5 | 79.3 | 57.7 |
| >-12.6 | 81.0 | 56.9 | 60.3 | 78.8 | 67.7 |
| >-12.1 | 62.1 | 76.4 | 68.0 | 71.4 | 70.0 |
| >-11.6 | 39.7 | 87.5 | 71.9 | 64.3 | 66.2 |
| >-11.1 | 17.2 | 98.6 | 90.9 | 59.6 | 62.3 |
| >-10.6 | 5.2 | 100.0 | 10.0 | 56.7 | 57.7 |
| HCnorm | |||||
| ≤91 | 93.1 | 23.6 | 49.6 | 80.9 | 54.6 |
| ≤82 | 89.7 | 30.6 | 51.0 | 78.6 | 56.9 |
| ≤73 | 87.9 | 37.5 | 53.2 | 79.4 | 60.0 |
| ≤64 | 82.8 | 43.1 | 54.0 | 75.6 | 60.8 |
| ≤55 | 79.3 | 51.4 | 56.8 | 75.5 | 63.8 |
| ≤46 | 74.1 | 56.9 | 58.1 | 73.2 | 64.6 |
| ≤37 | 70.7 | 65.3 | 62.2 | 73.4 | 67.7 |
| ≤28 | 69.0 | 72.2 | 66.7 | 74.3 | 70.8 |
| ≤19 | 60.6 | 76.4 | 67.3 | 70.5 | 69.2 |
| ≤10 | 44.8 | 84.7 | 70.3 | 65.6 | 66.9 |
Notes: The results of exploration on how the sensitivity, specificity, positive predictive value, negative predictive value and accuracy change as the HCage increases from −14.6 to −10.6 by 0.5. Y =12.047+ −0.087X1 + −14.192X2, where Y is the prediction score of HCage, X1 is age, and X2 is %HC/ICV.
Abbreviations: Aβ, beta-amyloid; HCnorm, normative percentiles of hippocampal volume.