Predictive indices under different combinations of overall disease probability (<i>K</i>) and variance explained ().

AUC accurate, accurate AUC obtained by the integration formula as described in text; AUC approx, AUC approximated by binormal curve and assuming equal variance in cases and controls; AUC approx2, AUC approximated by binormal curve and unequal variance in cases and controls. Prop cases exp 0.1, proportion of cases explained by the people at top 10% of risk; similar abbreviations used for the next 2 items. Var : variance ; max, maximum ; Diff, difference; RR, relative risk.