A newer alternative to the traditional bleeding time test is the platelet function screen performed on the PFA-100 analyzer.
[3] The test involves cutting the underside of the subject's forearm, in an area where there is no hair or visible veins.
[6] A prolonged bleeding time may be a result from decreased number of thrombocytes or impaired blood vessels.
[7] With the Duke's method, the patient is pricked with a special needle or lancet, preferably on the earlobe[8] or fingertip, after having been swabbed with alcohol.
[7] Bleeding time may be affected by platelet function, certain vascular disorders and von Willebrand Disease—not by other coagulation factors such as haemophilia.
While warfarin and heparin have their major effects on coagulation factors, an increased bleeding time is sometimes seen with use of these medications as well.
[10] In the British comedy film Doctor in the House (1954), Sir Lancelot Spratt, the intimidating chief of surgery played by James Robertson Justice is asking instructional questions of his medical students.