Table 7.
Diagnostic classification accuracy based on time and/or error scores on Trail Making Test Part B
| Sensitivity | Specificity | PPP | NPP | Hit Rate | |
|---|---|---|---|---|---|
| MCI/AD (n=257) vs. Control (n=269) | |||||
| Errors1 | 61.9% | 70.3% | 66.5% | 65.9% | 66.2% |
| Time2 | 45.1% | 91.1% | 82.9% | 63.5% | 68.6% |
| Errors and time3 | 35.4% | 94.4% | 85.8% | 60.5% | 75.5% |
| Errors and/or time4 | 71.6% | 66.9% | 67.4% | 71.1% | 69.2% |
| MCI (n=200) vs. Control (n=269) | |||||
| Errors1 | 59.0% | 70.3% | 59.6% | 69.7% | 65.5% |
| Time2 | 43.0% | 91.1% | 78.2% | 68.2% | 70.6% |
| Errors and time3 | 33.0% | 94.4% | 81.5% | 65.5% | 76.2% |
| Errors and/or time4 | 69.0% | 66.9% | 60.8% | 74.4% | 67.8% |
| AD (n=57) vs. MCI (n=200) | |||||
| Errors1 | 71.9% | 41.0% | 25.8% | 83.7% | 47.9% |
| Time2 | 52.6% | 57.0% | 25.9% | 80.9% | 56.0% |
| Errors and time3 | 43.9% | 67.0% | 27.5% | 80.7% | 53.0% |
| Errors and/or time4 | 80.7% | 31.0% | 25.0% | 84.9% | 42.0% |
Note: MCI = mild cognitive impairment; AD = Alzheimer’s disease; PPP = positive predictive power; NPP = negative predictive power.
Identification of impairment within each condition was based on the following contrasts:
1
≥1 error vs. 0 errors
2
z≤−1.0 vs. z >−1.0
3
≥1 error and z ≤ −1.0 vs. 0 errors and z>−1.0
4
≥1 error and/or z ≤ −1.0 vs. 0 errors and z>−1.0