Abstract:

Objective To investigate the evaluation method for measurement uncertainty of serum total bilirubin （TBil） concentration in clinical reference laboratories．Methods The International Federation of Clinical Chemistry and Laboratory Medicine（IFCC） external quality assessment scheme for reference laboratories in laboratory medicine（RELA）sample was measured by Doumas serum TBil reference procedure of the Joint Committee for Traceability in Laboratory Medicine（JCTLM）,and the sources of uncertainty components were identified. The evaluation of uncertainty components was processed,and then a combined standard uncertainty was calculated. Finally,an expanded uncertainty was obtained．Results The TBil average concentration of 2013 RELA-A sample was 52.30 μmol/L,the combined standard uncertainty was 0.67 μmol/L,the 95% confidence interval was taken,and the coverage factor（k）was 2. The expanded uncertainty was 1.34 μmol/L. The TBil average concentration of 2013 RELA-B sample was 81.60 μmol/L,the combined standard uncertainty was 0.70 μmol/L,the 95% confidence interval was taken,and the k was 2. The expanded uncertainty was 1.40 μmol/L．Conclusions The established method can meet the requirements of clinical laboratories for serum TBil reference procedure.

Key words: Total bilirubin, Serum, Reference procedure, Measurement uncertainty evaluation