Other names for Factors I, II, III, and IV
Factor Other name
I Fibrinogen
II Prothrombin
III Tissue Factor
IV Calcium








Most common bleeding disorders
Bleeding disorder Incidence
Von Willebrand Disease 0.5 - 2% of general population
Hemophilia A and B 1 in 5000 males
1 in 10,000 overall
Hemophilia A is 4 times more common


Reference 1, 2
Types of VWD and their characteristics
Type I VWD
  • Defect: Mild-moderate deficiency (5-30% reduction) of VWF and Factor VIII
  • Transmission: Autosomal dominant
  • Bleeding severity: Mild to moderate
  • % of affected individuals: 60 - 80%
Type II VWD
  • Defect: Qualitative defect of VWF
  • Transmission: Autosomal dominant
  • Bleeding severity: Typically moderate
  • % of affected individuals: 10 - 30%
Type III VWD
  • Defect: Severe or complete deficiency of VWF and moderately severe Factor VIII deficiency
  • Transmission: Autosomal recessive
  • Bleeding severity: Severe
  • % of affected individuals: 1 - 5%%




Reference 4, 5
Prevalence of hypercoagulable risk factors
Disorder % of general population % of patients with blood clots
High concentration of Factor VIII 11% 25%
Antiphospholipid antibodies unknown 24%
Factor V Leiden 5% 20%
Hyper-homocysteinemia 5% 10%
Prothrombin 20210A 2% 6%
Protein C deficiency 0.2-0.4% 3%
Protein S deficiency unknown unknown
Antithrombin deficiency 0.02% 1%