The most common subtype of classic von Willebrand's disease is:

The most common subtype of classic von Willebrand's disease is Type 1. This form of the disease is characterized by a partial deficiency of von Willebrand factor (vWF), a key protein involved in hemostasis that facilitates platelet adhesion to sites of vascular injury. Patients with Type 1 generally have mild bleeding symptoms due to the reduced levels of vWF, but they often respond well to treatment with desmopressin, which increases the release of vWF from endothelial cells.

Type 1 von Willebrand's disease represents the milder end of the spectrum where the majority of patients present with a quantitative deficiency, leading to a more common occurrence compared to the other subtypes. Type 2A and Type 2B involve qualitative defects of the vWF, which can result in more severe bleeding issues due to changes in the function of the protein. Type 3 is the most severe form of von Willebrand's disease, characterized by a complete absence of vWF, and is much less common than Type 1. Thus, Type 1's prevalence and the nature of its deficiency confirm it as the most common subtype of classic von Willebrand's disease.