Certified Value for T₄ and T₃ in CHT EQA Survey

The certified value of Thyroxine ( T4 ) or Triiodothyronine ( T3 ) in serum was determined using Isotope Dilution Mass Spectrometry (IDMS) reference method* by an international certified reference laboratory. The reference laboratory is signatory to the multilateral agreements of the European co-operation for Accreditation (EA) and of the International Laboratory Accreditation Cooperation (ILAC) for the mutual recognition of calibration certificates. The uncertainty stated is the expanded uncertainty obtained by multiplying the standard uncertainty by the coverage factor k. At a t-distribution with veff effective degrees of freedom the value of the measurand lies within the assigned range of values with a probability of 95%. It has been determined in accordance with EAL-R2 and EA-4/02. * Thienpont LM, Van Uytfanghe K, Beastall G, et.al.  Report of the IFCC Working Group for Standardization of Thyroid Function Tests; Part 3:Total Thyroxine and Total Triiodothyronine. Clin Chem 2010; 56: 921 – 9.   此品管檢體 T4 或 T3 的設定值為國際認證的參考實驗室使用同位素稀釋質譜分析 ( Isotope dilution mass spectrometry; IDMS )  標準參考方法*標定。 該參考實驗室為歐洲認證聯盟 ( European co-operation for Accreditation; EA ) 及國際實驗室認證聯盟 ( International Laboratory Accreditation Cooperation; ILAC )  認證之參考實驗室。 表列之不確定度 ( uncertainty )為標準不確定度 ( standard uncertainty ) 乘以涵蓋因子 ( coverage factor : k ) 所得之擴充不確定度 ( expanded uncertainty，Ua )。被測量 ( measurand ) 值在有效自由度 ( veff ; effective degrees of freedom ) 之 t 分布 ( t-distribution ) 條件下，有 95% 的機率在標定範圍內。(依據 EAL-R2 及 EA-4/02 標準測定) * Thienpont LM, Van Uytfanghe K, Beastall G, et.al.  Report of the IFCC Working Group for Standardization of Thyroid Function Tests; Part 3:Total Thyroxine and Total Triiodothyronine. Clin Chem 2010; 56: 921 – 9.