A combination of screening laboratory tests

Screening (medicine)

Screening, in medicine, is a strategy used in a population to detect a disease in individuals without signs or symptoms of that disease. Unlike what generally happens in medicine, screening tests are performed on persons without any clinical sign of disease....

, designed to provide rapid non-specific information, which allows an initial broad categorization of haemostatic problems.

The basic screen consists of:

• platelet
  Platelet
  Platelets, or thrombocytes , are small,irregularly shaped clear cell fragments , 2–3 µm in diameter, which are derived from fragmentation of precursor megakaryocytes.  The average lifespan of a platelet is normally just 5 to 9 days...
  
   count
• bleeding time
  Bleeding time
  Bleeding time is a medical test done on someone to assess their platelet functionThe term "template bleeding time" is used when the test is performed to standardized parameters. This makes it easier to compare data collected at different facilities....
  
   for platelet function
• PR (prothrombin ratio) for extrinsic pathway
• aPTT (Activated Partial Thromboplastin time) for the intrinsic pathway
• TCT
  TCT
  TCT is a three-letter abbreviation which may refer to:* Teenage Cancer Trust* Texas City Terminal Railway* The Coroner's Toolkit, computer forensic software* The Catholic Transcript, a Hartford, CT catholic paper....
  
   or fibrinogen
  Fibrinogen
  Fibrinogen is a soluble plasma glycoprotein, synthesised by the liver, that is converted by thrombin into fibrin during blood coagulation. This is achieved through processes in the coagulation cascade that activate the zymogen prothrombin to the serine protease thrombin, which is responsible for...
  
   assay for final common pathway

Two other tests are regularly performed at the same time:

• blood count
  Blood Count
  "Blood Count" is a 1967 jazz composition by Billy Strayhorn. It was originally meant for a three-piece work Strayhorn was writing for Duke Ellington and initially titled "Blue Cloud". However, Strayhorn was hospitalized in 1967 due to cancer and finished the composition while in the hospital. He...
  
  , to detect other hematological abnormalities
• liver function tests
  Liver function tests
  Liver function tests , are groups of clinical biochemistry laboratory blood assays designed to give information about the state of a patient's liver. The parameters measured include PT/INR, aPTT, albumin, billirubin and others...
  
   to exclude liver disease
  Liver disease
  Liver disease is a broad term describing any single number of diseases affecting the liver.-Diseases:* Hepatitis, inflammation of the liver, caused mainly by various viruses but also by some poisons , autoimmunity or hereditary conditions...
  
   as a cause of coagulation factor deficiency

These tests may miss mild abnormalities but they will detect major disorders. The results of these screening tests, in conjunction with the clinical history (especially bleeding

Bleeding

Bleeding, technically known as hemorrhaging or haemorrhaging is the loss of blood or blood escape from the circulatory system...

 history), will then direct the selection of further, more detailed and specific coagulation tests, such as:

• specific factor assays, like fibrin degradation product
  Fibrin degradation product
  Fibrin degradation product , also known as fibrin split products, are components of the blood produced by clot degeneration.These are produced by the action of plasmin on deposited fibrin...
  
  s, D-dimer
  D-dimer
  D-dimer is a fibrin degradation product , a small protein fragment present in the blood after a blood clot is degraded by fibrinolysis. It is so named because it contains two crosslinked D fragments of the fibrinogen protein....
  
  , thrombin time, platelet aggregation, or
• specific factor inhibitor assays, like Protein C
  Protein C
  Protein C, also known as autoprothrombin IIA and blood coagulation factor XIV, is a zymogenic protein, the activated form of which plays an important role in regulating blood clotting, inflammation, cell death and maintaining the permeability of blood vessel walls in humans and other animals...
  
  , TFPI, Antithrombin
  Antithrombin
  Antithrombin is a small protein molecule that inactivates several enzymes of the coagulation system. Antithrombin is a glycoprotein produced by the liver and consists of 432 amino acids. It contains three disulfide bonds and a total of four possible glycosylation sites...
  
  etc.