Table 2.

Optimal FI Change Values for Predicting One-Level Change in CFS

Baseline to Admission	N with no CFS Change	N with +1 CFS Change	AUC Predicting +1 CFS Change (95% CI)	Change in FI with Highest J	J (Sensitivity, Specificity)
All	1,534	3,035	0.76 (0.74–0.77)	0.026	0.40 (0.70, 0.69)
Males	700	1,417	0.75 (0.73–0.77)	0.026	0.40 (0.69, 0.71)
Females	834	1,618	0.76 (0.75–0.78)	0.029	0.40 (0.65, 0.76)
Admission to Postdischarge	N with no CFS Change	N with -1 CFS Change	AUC Predicting -1 CFS Change (95% CI)	Change in FI with Highest J	J (Sensitivity, Specificity)
All	1,565	1,819	0.68 (0.66–0.70)	−0.032	0.27 (0.66, 0.61)
Males	716	855	0.67 (0.64–0.69)	−0.025	0.25 (0.75, 0.50)
Females	849	964	0.69 (0.66–0.71)	−0.031	0.30 (0.69, 0.61)

Note: Only patients who maintained or changed CFS by 1 level were included in this analysis. AUC = area under the ROC curve; CFS = Clinical Frailty Scale; CI = confidence interval; FI = Frailty Index; J = Youden Index value for the change in FI that best predicts a one-level change in CFS.