Table 5.

c-statistics for derivation and validation cohorts, stratified by outcome of prediction

Parsimonious Model
(95% CI)Short Model
(95% CI)P Value (Short versus Parsimonious)
Dialysis
 Derivation cohort (HUP 2004–2010)0.89 (0.88–0.91)0.88 (0.87–0.89)<0.001a
 Validation (PAH 2006–2010)0.89 (0.85–0.93)0.89 (0.85–0.93)0.48
 Validation (PMC 2004–2010)0.89 (0.86–0.92)0.88 (0.85–0.91)0.23
Death
 Derivation cohort (HUP 2004–2010)0.83 (0.82–0.84)0.80 (0.79–0.81)<0.001a
 Validation (PAH 2006–2010)0.83 (0.80–0.86)0.79 (0.76–0.83)<0.001
 Validation (PMC 2004–2010)0.82 (0.79–0.85)0.79 (0.75–0.82)<0.001
Dialysis or death
 Derivation cohort (HUP 2004–2010)0.85 (0.84–0.86)0.82 (0.81–0.83)<0.001a
 Validation (PAH 2006–2010)0.83 (0.80–0.86)0.77 (0.73–0.80)<0.001
 Validation (PMC 2004–2010)0.84 (0.82–0.86)0.80 (0.78–0.83)<0.001
  • P value reflects difference in predictive ability between short and parsimonious models. CI, confidence interval; HUP, Hospital of the University of Pennsylvania; PAH, Pennsylvania Hospital; PMC, Presbyterian Medical Center.

  • a P values may be unreliable in cohort from which model was derived