This guideline updates the previous guidelines1, 2 published on behalf of the British Society for Haematology (BSH) and the United Kingdom Haemophilia Centre Doctors' Organisation (UKHCDO), focusing on the laboratory components of diagnosis and monitoring. Clinical aspects will be addressed in a separate guideline.

This guideline describes laboratory tests used to diagnose and monitor individuals with von Willebrand disease (VWD). Since the publication of the previous guideline,1 new functional tests have become widely available as an alternative to the ristocetin cofactor assay. This guideline also updates genetic testing rationale and highlights the American College of Medical Genetics and Genomics (ACMG) guidelines for interpretation of sequence variants3, 4 and Association for Clinical Genomic Science (ACGS) guidelines for variant interpretation.5

Declaration of Interests

The BSH paid the expenses incurred during the writing of this guidance. None of the authors had conflicts of interest to declare. All authors have made a declaration of interests to the BSH and Task Force Chairs which may be viewed on request.