The Bethesda assay is used to measure the titer and activity of the antibody present in a patient's sample. Prothrombin time is an initial screening procedure for bleeding disorders and a test used for monitoring anticoagulant therapy. A thrombin time is used to detect heparin interference in an aPTT mixing study. A mixing study is performed to detect the presence of a factor deficiency or coagulation inhibitor, but does not quantify the result.

Hematology

Which of the following tests is used to quantify a coagulation inhibitor?