Table 3.
Cutoff Points of Frail and Not-Frail Patients Based on Fried Phenotype Frailty Assessment
| Direct Measurements | ||||||
|---|---|---|---|---|---|---|
| Characteristic | Cutoff | Sensitivity (95% CI) | Specificity (95% CI) | Negative Predictive value (95% CI) | Positive Predictive Value (95% CI) | Area under the Curve (95% CI) |
| Healthy controls | ||||||
| Quadriceps depth, cm | 2.3 | 0.94 (0.74, 0.99) | 0.64 (0.39, 0.84) | 0.90 (0.60, 0.98) | 0.77 (0.57, 0.90) | 0.80 (0.64, 0.97) |
| Rectus femoris cross-sectional area, cm2 | 6.2 | 1.00 (0.82, 1.00) | 0.57 (0.33, 0.79) | 1.00 (0.68, 1.00) | 0.75 (0.55, 0.88) | 0.70 (0.49, 0.91) |
| Psoas muscle area, cm2 | 18.5 | 0.78 (0.55, 0.91) | 0.93 (0.69, 0.99) | 0.76 (0.53, 0.90) | 0.93 (0.70, 0.99) | 0.88 (0.76, 1.00) |
| Rectus femoris circumference, cm | 12.9 | 0.89 (0.67, 0.97) | 0.57 (0.33, 0.79) | 0.80 (0.49, 0.94) | 0.73 (0.52, 0.87) | 0.67 (0.46, 0.88) |
| Normalized body mass index | ||||||
| Quadriceps depth, cm | 0.09 | 0.89 (0.67, 0.97) | 0.71 (0.45, 0.88) | 0.83 (0.55, 0.95) | 0.80 (0.58, 0.92) | 0.76 (0.57, 0.95) |
| Rectus femoris cross-sectional area, cm2 | 0.21 | 0.94 (0.74, 0.99) | 0.64 (0.39, 0.84) | 0.90 (0.60, 0.98) | 0.77 (0.57, 0.90) | 0.71 (0.50, 0.92) |
| Psoas muscle area | 0.55 | 0.50 (0.29, 0.71) | 1.00 (0.78, 1.00) | 0.61 (0.41, 0.78) | 1.00 (0.70, 1.00) | 0.80 (0.65, 0.95) |
| Rectus femoris circumference, cm | 0.44 | 0.67 (0.44, 0.84) | 0.64 (0.39, 0.84) | 0.60 (0.36, 0.80) | 0.71 (0.47, 0.87) | 0.61 (0.41, 0.82) |
| Normalized body surface area | ||||||
| Quadriceps depth, cm | 1.1 | 0.89 (0.67, 0.97) | 0.79 (0.52, 0.92) | 0.85 (0.58, 0.96) | 0.84 (0.62, 0.94) | 0.77 (0.58, 0.97) |
| Rectus femoris cross-sectional area, cm2 | 3.1 | 0.94 (0.74, 0.99) | 0.57 (0.33, 0.79) | 0.89 (0.57, 0.98) | 0.74 (0.54, 0.87) | 0.71 (0.51, 0.92) |
| Psoas muscle area | 9.7 | 0.89 (0.67, 0.97) | 0.93 (0.69, 0.99) | 0.87 (0.62, 0.96) | 0.94 (0.73, 0.99) | 0.95 (0.89, 1.00) |
| Rectus femoris circumference, cm | 6.7 | 0.78 (0.55, 0.91) | 0.57 (0.33, 0.79) | 0.67 (0.39, 0.86) | 0.70 (0.48, 0.85) | 0.63 (0.43, 0.84) |
Positive and negative predictive values were computed based on our sample frailty prevalence, which is likely not generalizable to the larger population. Our sample size was 32. The negative likelihood ratio is the ratio between the odds of a negative test result given the presence of frailty and the odds of a negative test result given the absence of frailty. The positive likelihood ratio is the ratio between the odds of a positive test result given the presence of frailty and the odds of a positive test result given the absence of frailty.