von Willebrand Disease, Type 1

**Semantic type:** Disease or Syndrome

**Definition:** An autosomally inherited (generally dominant) coagulation disorder characterized by quantitative partial deficiency of circulating von Willebrand factor (VWF) which account for 60 to 80% of cases of von Willebrand disease. It is characterized by mild to moderate quantitative deficiencies of VWF and factor VIII, which are coordinately reduced from normal plasma levels.