Table 2.
AUC-values, cut-off limits and their sensitivities, specificities and positive and negative predictive values for the 50-parameter combined index and for the reduced indexes in predicting 10-year institutionalization and mortality
| AUC (95% CI) | Cut-off limit (scale) | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | |
|---|---|---|---|---|---|---|
| Institutionalization | ||||||
| 50-parameter combined index |
0.71 (0.66–0.75) |
≥ 0.25* (0–1) |
38.3 | 84.9 | 29.4 | 89.3 |
| Reduced index without age and gender |
0.74 (0.70–0.78) |
≥ 2** (0–3) |
71.0 | 71.8 | 30.2 | 93.5 |
| Reduced index with age and gender |
0.78 (0.75–0.82) |
≥ 4** (0–7) |
74.7 | 69.4 | 29.6 | 94.1 |
| Mortality | ||||||
| 50-parameter combined index |
0.77 (0.74–0.80) |
≥ 0.25* (0–1) |
42.5 | 92.0 | 74.2 | 74.7 |
| Reduced index without age and gender |
0.79 (0.77–0.82) |
≥ 5** (0–9) |
61.8 | 84.2 | 69.5 | 79.2 |
| Reduced index with age and gender |
0.83 (0.80–0.85) |
≥ 8** (0–13) |
77.0 | 75.8 | 64.9 | 85.1 |
Abbreviations: AUC Area under the curve, CI Confidence interval, PPV Positive predictive value, NPV Negative predictive value
*Habitual cut-off limit for a frailty index
**Best cut-off limit defined by Youden-index