Table 4.
Derivation of a liver-specific frailty index: Candidate models incorporating various measures of physical frailty derived from best subsets selection with Cox regression.*
| Number of variables included | |||||||
|---|---|---|---|---|---|---|---|
| 2 | 3 | 3 | 4 | 4 | 5 | 6 | |
| Model # | #1 | #2 | #3† | #4 | #5 | #6 | #7 |
| Grip strength, per kg, gender-adjusted | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |
| Chair stands, number per second | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
| Balance, per second | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |
| Walk speed, per m/sec, gender-adjusted | ✔ | ||||||
| Exhaustion | |||||||
| Physical activity | ✔ | ✔ | ✔ | ||||
| Unintentional weight loss | |||||||
| ADLs, per ADL | ✔ | ✔ | |||||
| Independent IADL, per IADL | ✔ | ✔ | |||||
| AIC | 1113 | 1112 | 1117 | 1113 | 1113 | 1112 | 1113 |
| C-statistic | 0.72 (0.67–0.77) |
0.72 (0.67–0.77) |
0.71 (0.61–0.82) |
0.72 (0.68–0.77) |
0.72 (0.66–0.78) |
0.72 (0.68–0.78) |
0.73 (0.67–0.78) |
*
As a point of reference, in our cohort, the AIC and C-statistic (including all follow-up time) for MELDNa was 1126 and 0.70, respectively. Higher AIC indicates relative lower model quality.
†
This model was not among the highest performing models by AIC using best subset selection but is included here to demonstrate performance characteristics of a performance-based model that does not require any specialized equipment for testing.