Kaplan-Meier survival curves for grades of the FI. A) Survival over the course of the study plotted as a function of grades of the FI-CSHA. The least frail group (frailty score <0.10) showed little mortality over the course of the study whereas the most frail group (frailty score >0.45) showed very high mortality. Differences between groups were statistically significant between all four grades of frailty when analyzed with a log-rank test (P <0.05). B) Survival curves for grades of frailty assessed by the FI-LAB scores. There were significant differences in survival between subjects at all four levels when FI-LAB scores were used to grade frailty (P <0.05; log rank test). C) Kaplan-Meier survival curves for `combined’ FI scores obtained by merging the FI-CSHA and the FI-LAB scores. Differences in mortality between the four grades of frailty were most evident when the combination FI scores were used (P <0.05; log rank test). FI-CSHA, standard frailty index; FI-LAB, laboratory frailty index.