Table 2.
AUCs for All Classification Models in Test and Clinical Cohorts.
| Model: | Test Cohort AUCs (95% CI) | Clinical Cohort AUCs (95% CI) |
|---|---|---|
| Age | 0.675 | 0.742 |
| (0.572–0.778) | (0.694–0.790) | |
| HCV | 0.944 | 0.801 |
| (0.902–0.987) | (0.756–0.846) | |
| SARA | 0.961 | 0.820 |
| (0.925–0.997) | (0.776–0.864) | |
| HCV + Age | 0.950 | 0.792 |
| (0.909–0.991) | (0.747–0.838) | |
| SARA + Age | 0.962 | 0.799 |
| (0.924–0.999) | (0.753–0.845) | |
| HCVadj | 0.948 | 0.743 |
| (0.905–0.992) | (0.693–0.792) | |
| SARAadj | 0.952 | 0.764 |
| (0.911–0.993) | (0.714–0.813) | |
| HCVadj + Age | 0.949 | 0.793 |
| (0.908–0.991) | (0.748–0.840) | |
| SARAadj + Age | 0.961 | 0.799 |
| (0.925–0.997) | (0.752–0.845) |
Table 2 displays each model's AUC (for AD vs. non-AD diagnoses) in the Test Cohort and Clinical Cohort along with its associated 95% CI. The AUC of an ROC plot (not displayed) gives a measure of model performance that does not depend on a specific cut-off or threshold. The various SARA models include hippocampal volume, inferior lateral ventricle volume, entorhinal thickness, amygdala volume, and inferior parietal thickness. X + Age indicates model X with age added as a covariate; Xadj indicates Model X using volumes and cortical thicknesses that have been adjusted for age-related atrophy.
Abbreviations: AD – Alzheimer disease; AUC – Receiver Operating Characteristics Area Under the Curve; CI – Confidence Interval; HCV – Hippocampal Volume; SARA – Select Atrophied Regions in Alzheimer disease