Receiver operating characteristic analysis. Receiver operating characteristic curve analysis of FXI:C alone, APTT alone, APTT+Vmax from fibrinolysis assays (model 1, APTT+Vmax_tPA), and APTT plus Vmax and AUC from fibrinolysis assays (model 2, APTT+Vmax_tPA+AUC_tPA). FXI:C and APTT were measured without CTI. Models 1 and 2 show assay results from plasmas collected in the (A) presence or (B) absence of CTI.