label: Prolonged partial thromboplastin time
label_lc: prolonged partial thromboplastin time
description: "Increased time to coagulation in the partial thromboplastin time (PTT) test, a measure of the intrinsic and common coagulation pathways. Phospholipid, and activator, and calcium are mixed into an anticoagulated plasma sample, and the time is measured until a thrombus forms."