Correlation of blood group and sex with plasma levels of VWF. (A-D) Correlation between blood groups and VWF-related measurements in plasma samples obtained from the donors. The number of individuals with blood groups A, AB, B, and O were 14, 3, 9, and 17, respectively. (E) Correlation between sex and VWF-related measurements. Statistical analysis was performed using a 2-tailed t test. n.s., not significant.