Table 9. DOC-Cog results.
Diagnostic Characteristics | Single cut-point (raw scores) | Single cut-point (regression) | Two cut-points (raw scores) | Two cut-points (regression) |
---|---|---|---|---|
AUC | 0.776 | 0.814 | 0.776 | 0.814 |
High-risk | Raw score 0–8 | POI e > .122 | Raw score 0–5 | POI e > .26 |
% of population | 180 (47%) | 180 (47%) | 28 (7%) | 58 (15%) |
Impaired | 44 (24%) | 47 (26%) | 12 (41%) | 25(42%) |
Not Impaired | 136 (76%) | 133 (74%) | 16 (59%) | 33 (58%) |
Specificity | 59% | 61% | 95% | 91% |
+LR a | 2 | 2.2 | 4.7 | 4.8 |
PPV b | 24% | 26% | 43% | 43% |
Intermediate-risk | N/A f | N/A f | Raw score 6–9 | POI e .08-.26 |
% of population | N/A f | N/A f | 254 (66%) | 178 (46%) |
Impaired | N/A f | N/A f | 41 (16%) | 26 (15%) |
Not Impaired | N/A f | N/A f | 213 (84%) | 152 (85%) |
Specificity/Sensitivity | N/A f | N/A f | N/A g | N/A g |
+/-LR ac | N/A f | N/A f | N/A g | N/A g |
PPV/NPV bd | N/A f | N/A f | N/A g | N/A g |
Low-risk | Raw score 9–10 | POI e < .122 | Raw score 10 | POI e < .08 |
% of population | 207 (53%) | 207 (53%) | 105 (27%) | 151 (39%) |
Impaired | 9 (4%) | 6 (3%) | 0 (0%) | 2 (1%) |
Not Impaired | 198 (96%) | 201 (97%) | 105 (100%) | 149 (99%) |
Sensitivity | 83% | 88% | 100% | 96% |
-LR c | 0.3 | 0.2 | 1.5 | 1.7 |
NPV d | 96% | 97% | 100% | 99% |
a +LR = positive likelihood ratio,
b PPV = positive predictive value,
c -LR = negative likelihood ratio,
d NPV = negative predictive value,
e POI = probability of impairment,
f N/A, no intermediate group using single cut-point method,
g cannot calculate statistics for intermediate group