Pathology Handbook

Coagulation Factor assays

Synonyms

  • F2, Factor 2, FII

  • F5, Factor 5, FV

  • F7, Factor 7, FVII

  • F8, Factor 8, FVIII,  Haemophilic factor

  • F9, Factor 9, FIX, Christmas factor

  • F10, Factor 10, FX

  • F11, Factor 11, FXI

  • F12, Factor 12, FXII

Clinical Indications 

Unexplained bruising/bleeding, prolonged routine clotting results.

It is strongly suggested to request a Bleeding disorder screen instead of individual assays unless investigating a known case

Please note FV assay is NOT the same as FV Leiden assay (see Thrombophilia screen)

Please note FX assay is NOT the same Anti-Xa assay (See Anti-Xa assay) 

Request Form 

Request via ICE

Availability

Mon - Fri 9AM to 4PM

Specific Criteria

Patient should be bled with minimal stasis

Patient Preparation

None

Turnaround Time

Screen performed within 4 weeks of receipt and may require further samples and referral to Consultant Haematologist or to a specialist centre.

Specimen

Fresh citrated Blood (within 2 hours of collection)

Volume

4.5 ml

Container

 Blue capped vacutainer tubes

Vacutainer blue top

Collection

Clean venepuncture; sample transported to laboratory immediately after collection

Causes for Rejection

Under-filled, clotted or haemolysed samples

Reference Range

See patient test report