Table 4. Comparison of the areas under the receiver operating characteristic (ROC) curves of the four frailty instruments compared.* .
| Frailty index | AUC | SE | 95% CI | Contrast p-value | |||||
| Follow-up | Crude/Adjusted Models | 1 vs 2 | 1 vs 3 | 1 vs 4 | |||||
| 1.MPI | 0.7486 | 0.0209 | 0.71–0.79 | ||||||
| Overall | 2. FI-SOF | 0.5918 | 0.0208 | 0.55–0.63 | <0.0001 | <0.0001 | <0.0001 | ||
| 3.FI-CD | 0.7094 | 0.0208 | 0.67–0.75 | ||||||
| 4.FI-CGA | 0.6924 | 0.0218 | 0.65–0.73 | ||||||
| 1.MPI | 0.7396 | 0.0332 | 0.67–0.80 | ||||||
| Male | 2. FI-SOF | 0.6163 | 0.0313 | 0.55–0.67 | 0.0002 | 0.0017 | 0.0094 | ||
| Unadjusted | 3.FI-CD | 0.7013 | 0.0333 | 0.64–0.77 | |||||
| 4.FI-CGA | 0.6923 | 0.0340 | 0.62–0.76 | ||||||
| 1 month | 1.MPI | 0.7636 | 0.0260 | 0.71–0.81 | |||||
| Female | 2. FI-SOF | 0.5749 | 0.0279 | 0.52–0.63 | <0.0001 | 0.0051 | <0.0001 | ||
| 3.FI-CD | 0.7216 | 0.0259 | 0.67–0.77 | ||||||
| 4.FI-CGA | 0.6994 | 0.0282 | 0.64–0.76 | ||||||
| 1.MPI | 0.7655 | 0.0203 | 0.72–0.80 | ||||||
| Age- and sex- | Overall | 2. FI-SOF | 0.6854 | 0.0221 | 0.64–0.73 | <0.0001 | 0.0005 | <0.0001 | |
| adjusted | 3.FI-CD | 0.7383 | 0.0204 | 0.69–0.78 | |||||
| 4.FI-CGA | 0.7240 | 0.0215 | 0.68–0.77 | ||||||
| 1.MPI | 0.7231 | 0.0141 | 0.69–0.75 | ||||||
| Overall | 2. FI-SOF | 0.6034 | 0.0142 | 0.57–0.63 | <0.0001 | <0.0001 | <0.0001 | ||
| 3.FI-CD | 0.6934 | 0.0143 | 0.66–0.72 | ||||||
| 4.FI-CGA | 0.6890 | 0.0145 | 0.66–0.72 | ||||||
| Unadjusted | 1.MPI | 0.7164 | 0.0213 | 0.67–0.76 | |||||
| 1 year | Male | 2. FI-SOF | 0.6196 | 0.0210 | 0.58–0.66 | <0.0001 | 0.0010 | 0.0048 | |
| 3.FI-CD | 0.6836 | 0.0221 | 0.64–0.73 | ||||||
| 4.FI-CGA | 0.6855 | 0.0219 | 0.64–0.73 | ||||||
| 1.MPI | 0.7416 | 0.0184 | 0.70–0.78 | ||||||
| Female | 2. FI-SOF | 0.5974 | 0.0193 | 0.56–0.63 | <0.0001 | 0.0005 | 0.0003 | ||
| 3.FI-CD | 0.7081 | 0.0184 | 0.67–0.74 | ||||||
| 4.FI-CGA | 0.7042 | 0.0189 | 0.67–0.74 | ||||||
| 1.MPI | 0.7507 | 0.0135 | 0.72–0.78 | ||||||
| Age- and sex- | Overall | 2. FI-SOF | 0.6948 | 0.0142 | 0.67–0.72 | <0.0001 | <0.0001 | <0.0001 | |
| adjusted | 3.FI-CD | 0.7297 | 0.0138 | 0.70–0.76 | |||||
| 4.FI-CGA | 0.7278 | 0.0139 | 0.70–0.75 | ||||||
AUC: areas under curve; SE: standard error; CI: confidence interval; MPI: Multidimensional Prognostic Index; FI-SOF: Frailty Index derived from the Study of Osteoporotic Fractures; FI-CD: Frailty Index based on cumulative deficits; FI-CGA: Frailty Index based on a Comprehensive Geriatric Assessment.
*AUCs were assessed by crude and adjusted logistic regression models, accounting for clustering due to centre effect.