ROC analysis showing sensitivity, specificity, PPV, and NPV for abnormal outcome of multiple cutoff levels of ADC (in 10−6/mm2/s) of the basal ganglia*
| Cutoff Level | Sensitivity | 95% CI† | Specificity | 95% CI† | PPV | NPV |
|---|---|---|---|---|---|---|
| <574 | 6.67 | 1.1–32.0 | 100.00 | 54.1–100.0 | 100.0 | 30.0 |
| <1018.5 | 66.67 | 38.4–88.1 | 100.00 | 54.1–100.0 | 100.0 | 54.5 |
| <1036.5 | 66.67 | 38.4–88.1 | 83.33 | 36.1–97.2 | 90.9 | 50.0 |
| <1109.5 | 80.00 | 51.9–95.4 | 50.00 | 12.4–87.6 | 80.0 | 50.0 |
| <1174 | 86.67 | 59.5–98.0 | 16.67 | 2.8–63.9 | 72.2 | 33.3 |
| <1239 | 93.33 | 68.0–98.9 | 0.00 | 0.0–45.9 | 70.0 | 0.0 |
Note:—ROC indicates receiver operating characteristic analysis; CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value.
* Area under the ROC curve = 0.767. Significance level P (area = 0.5) = .0347.
† 95% CI = 0.533–0.920.