The time required for the appearance of FIBRIN strands following the mixing of PLASMA with phospholipid platelet substitute (e.g., crude cephalins, soybean phosphatides). It is a test of the intrinsic pathway (factors VIII, IX, XI, and XII) and the common pathway (fibrinogen, prothrombin, factors V and X) of BLOOD COAGULATION. It is used as a screening test and to monitor HEPARIN therapy.

Synonyms: Cephalin-Kaolin Coagulation Time, Cephalin Kaolin Coagulation Time, Kaolin-Cephalin Coagulation Time, Partial Thromboplastin Time, Coagulation Time, Cephalin Kaolin, Kaolin Cephalin Coagulation Time, Coagulation Time, Cephalin-Kaolin, Coagulation Time, Kaolin-Cephalin, Thromboplastin Time, Partial, Activated Partial Thromboplastin Time