Table 2.

Performance of the Ensemble Index, Charlson Comorbidity Index, and Walter life expectancy method for predicting 5 year survival, and reclassifications by the Ensemble Index

Evaluation metric	Walter life expectancy method	Charlson Comorbidity Index	Ensemble Index
C statistic (95% CI)	0.78(0.77 to 0.80)*	0.81 (0.79 to 0.83)*	0.86 (0.85 to 0.87)
Sensitivity (recall) (%)	22.8	13.1	30.7
Specificity (%)	96.8	98.5	97.7
Positive predictive value (precision) (%)	47.0	52.6	63.0
Negative predictive value (%)	90.8	90.0	91.8
F measure (%)	30.7	21.0	41.3
Correct predictions (%)	88.4	88.9	90.2
No of individuals reclassified by the Ensemble Index
Events moved to life expectancy <5 years	144	181	Reference
Events moved to life expectancy >5 years	78	34	Reference
Non-events moved to life expectancy <5 years	99	110	Reference
Non-events moved to life expectancy >5 years	163	59	Reference
Net reclassification improvement (%)	8.8†	16.8†	–

*p<0.001 for comparison with Ensemble Index; †p<0.001.