Predictive ability of the OFS compared with other indices for 30-day mortality
| Index | AUC (95% CI) | Sensitivity (95% CI) | Specificity (95% CI) | P value for difference in AUC |
| OFS | 0.77 (0.74 to 0.80) | 0.84 (0.78 to 0.89) | 0.56 (0.49 to 0.61) | Reference |
| NHFS | 0.76 (0.73 to 0.79) | 0.67 (0.60 to 0.74) | 0.71 (0.65 to 0.76) | 0.620 |
| Sernbo Score | 0.73 (0.69 to 0.76) | 0.64 (0.57 to 0.71) | 0.71 (0.63 to 0.75) | 0.011 |
| CCI | 0.69 (0.66 to 0.73) | 0.55 (0.48 to 0.63) | 0.72 (0.65 to 0.77) | <0.001 |
| 5-mFI | 0.69 (0.66 to 0.73) | 0.71 (0.64 to 0.78) | 0.57 (0.49 to 0.62) | <0.001 |
| ASA Classification | 0.67 (0.64 to 0.71) | 0.75 (0.68 to 0.81) | 0.50 (0.41 to 0.56) | <0.001 |
| RCRI | 0.59 (0.55 to 0.63) | 0.62 (0.55 to 0.69) | 0.51 (0.43 to 0.58) | <0.001 |
ASA, American Society of Anesthesiologists; AUC, area under the receiver-operating characteristic curve; CCI, Charlson Comorbidity Index; 5-mFI, 5-factor modified Frailty Index; NHFS, Nottingham Hip Fracture Score; OFS, Orthopedic Hip Frailty Score; RCRI, Revised Cardiac Risk Index.