Armand J. Quick: pioneer and prophet of coagulation research.

During a professional career spanning more that 50 years, the American physician, biochemist, and teacher Armand J. Quick made numerous important contributions to medicine, particularly in the field of hemostasis. His hippuric acid test (1933) was the first quantitative test of liver function. In 1935 he reported the technique most closely associated with his name, the prothrombin time test, which was used by other investigators in the isolation of vitamin K and the identification of the coumarin anticoagulants. Later the test came into wide use for the control of anticoagulant therapy. Quick studied hereditary bleeding disorders and devised tests for their identification. He also uncovered several basic principles of normal hemostasis. He was among the first to draw attention to the anticoagulant properties of aspirin, and at the end of his career postulated the existence of a vitamin besides C and K that is essential for hemostasis.