Plasma VWF:Act/VWF:Ag ratios in patients with low VWF–QL. (A) VWF:Act and VWF:Ag levels in the total low VWF cohort (n = 214) at the time of diagnosis. The purple area indicates the subset of patients with low VWF with VWF:Act/VWF:Ag ratios of <0.7. The orange area indicates the subset of patients with low VWF–QL with VWF:Act/VWF:Ag ratios of ≥0.7. (B) The ISTH-BAT bleeding scores among patients with low VWF–QL with VWF:Act/VWF:Ag ratios of ≥0.7 and <0.7. The P value was determined using an independent t test.