Proposal of a Candidate International Conventional Reference Measurement Procedure for Free Thyroxine in Serum1)

The IFCC Working Group on Standardization of Thyroid Function Tests (WG-STFT) is mandated with establishing metrological traceability of measurement procedures for free thyroxine (FT4) in plasma/serum. In this document, the WG-STFT proposes and gives the rationale to establish metrological traceability of free thyroxine measurements in plasma/serum to a standard measurement procedure.JRC.D.2-Reference material