Process
It involves cutting the underside of the subject's forearm, in an area where there is no hair or visible veins. The cut is of a standardized width and depth, and is done quickly by an automatic device.
A blood pressure cuff is used above the wound, to maintain venous pressure at a special value. The time it takes for bleeding to stop (i.e. the time it takes for a platelet plug to form) is measured. Cessation of bleeding can be determined by blotting away the blood every several seconds until the site looks 'glassy'.
Read more about this topic: Bleeding Time
Famous quotes containing the word process:
“Yet I doubt not through the ages one increasing purpose runs,
And the thoughts of men are widened with the process of the suns.”
—Alfred Tennyson (1809–1892)
“... the history of the race, from infancy through its stages of barbarism, heathenism, civilization, and Christianity, is a process of suffering, as the lower principles of humanity are gradually subjected to the higher.”
—Catherine E. Beecher (1800–1878)
“The invention of photography provided a radically new picture-making process—a process based not on synthesis but on selection. The difference was a basic one. Paintings were made—constructed from a storehouse of traditional schemes and skills and attitudes—but photographs, as the man on the street put, were taken.”
—Jean Szarkowski (b. 1925)