Final answer:
Type I von Willebrand disease is characterized by a deficiency or dysfunction of von Willebrand factor (vWF), a protein that helps platelets stick to the blood vessel walls and form clots. Multimer analysis is a laboratory test that measures the size distribution of vWF multimers, which are formed when vWF molecules stick together.
Step-by-step explanation:
Type I von Willebrand disease is characterized by a deficiency or dysfunction of von Willebrand factor (vWF), a protein that helps platelets stick to the blood vessel walls and form clots. In this disorder, the vWF is either reduced in quantity or doesn't work properly.
Multimer analysis is a laboratory test that measures the size distribution of vWF multimers, which are formed when vWF molecules stick together. In type I vW disease, multimer analysis typically shows a decrease in the size of the vWF multimers, indicating a deficiency of vWF.