Table 3.

Comparison of area under receiver operator characteristic curves for the Charlson and Elixhauser Comorbidity Indices as predictors of mortality at various time points

	Charlson Comorbidity Index	Elixhauser Comorbidity Index	p Value
30-day mortality	0.65 (0.65 to 0.66)	0.66 (0.65 to 0.67)	0.02
90-day mortality	0.69 (0.68 to 0.70)	0.71 (0.70 to 0.71)	<0.001
180-day mortality	0.71 (0.70 to 0.71)	0.72 (0.71 to 0.72)	<0.001
365-day morality	0.72 (0.71 to 0.72)	0.72 (0.72 to 0.72)	0.46

Values represent area under the curve with 95% CIs in parentheses. p Values calculated by testing the difference between the areas under the curve using a t test.