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Von Willebrand Factor

Blood Sciences Test


Sodium Citrate

Special Instructions

3 x citrate blood tubes

Factors affecting results

Haemolysed or clotted samples cannot be tested. To avoid haemolysis and clotted samples mix tube gently by inversion, do not shake.

Reference Range

Von Willebrand antigen assay

Blood Group O                  42.0 – 140.8%

Blood Group A +B+AB      66.1- 176.3%

Von Willebrand activity assay

Blood Group O                  48.2-201.9%

Blood Group A +B+AB      60.8-239.8%

From : Williams M, Chalmers E,Gibson B  British Journal of Haematology 2002 119: 295 – 309,Andrew M et al Blood 1992 80: 1998 – 2005

Test Usage

To aid in the diagnosis of Von Willebrand Disease

Turnaround time

14 days

Urgent samples may be tested by arrangement with a Consultant Haematologist


In House

Clinical Advice

Clinical advice is available from the Haematology Medical team (contact RD&E switchboard on 01392 411611)

Specimen Labelling Procedure
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