Table 1.
Performance of Medicare Claims-Based Algorithm for Identifying Dementia Compared With Rush Alzheimer’s Disease Center Dementia Evaluations, 2016a,b
| Dementia Status in Cohort Evaluation | Sensitivity (95% CI) | Specificity (95% CI) | Positive Predictive Value (95% CI) | Negative Predictive Value (95% CI) | Accuracy (95% CI) | Kappa (95% CI) | |||
|---|---|---|---|---|---|---|---|---|---|
| Dementia status in claims | Yes | No | Total | ||||||
| 1-y windowb | 64% (56, 72%) | 93% (92, 95%) | 58% (51, 66%) | 95% (93, 96%) | 89% (88, 91%) | 0.55 (0.48, 0.62) | |||
| Yes | 92 | 66 | 158 | ||||||
| No | 52 | 908 | 960 | ||||||
| Total | 144 | 974 | 1 118 | ||||||
| 3-y windowb | 79% (73, 86%) | 88% (86, 90%) | 50% (43, 56%) | 97% (95, 98%) | 87% (85, 89%) | 0.54 (0.47, 0.61) | |||
| Yes | 108 | 109 | 217 | ||||||
| No | 28 | 809 | 837 | ||||||
| Total | 136 | 918 | 1 054 |
aDementia status in cohort evaluations represents all prevalent dementia cases identified as of 2016 who met standard clinical criteria as part of annual neurologic/neuropsychologic assessments.
bDementia status in claims represents prevalent cases of dementia identified using a validated algorithm in Medicare claims files. Dementia status was defined either using claims within a 1-y window of the 2016 Cohort evaluation (ie, ±6 mo) or using claims within a 3-y window (ie, ±18 mo).