Pedigree and biochemical analysis. (A) A 3-generation pedigree with VWD. Shaded symbols represent affected individuals diagnosed with VWD based on the levels of VWF antigen and ristocetin cofactor activities. Compared with the nonaffected family members, the affected individuals on average had a decreased level of VWF in plasma (B); a lower ratio of ristocetin cofactor activity to VWF antigen (F); decreased binding to recombinant GPIbα (G), collagen III (H), and collagen VI (I); and decreased factor VIII coagulation activity (C), but a slightly higher ratio of VWF propeptide to VWF antigen (E) and similar ADAMTS13 activity (D). The bottom and top of the boxes represent the first and third quartiles, respectively, of the values; the line inside the box indicates the median; and the end of the whiskers show the range of values that lie within 1.5-fold of the interquartile range of the median.