Ann Lab Med.  2012 Jul;32(4):243-249. 10.3343/alm.2012.32.4.243.

Trueness Assessment for Serum Glucose Measurement Using Commercial Systems through the Preparation of Commutable Reference Materials

• Xia C
• Liu O
• Wang L
• Xu G

• KMID: 1380082
• DOI: http://doi.org/10.3343/alm.2012.32.4.243

Abstract

BACKGROUND
Commutable reference materials (RMs) are suitable for end-users for evaluating the metrological traceability of values obtained using routine measurement systems. We assessed the performance of 6 routine measurement systems with validated secondary RMs.
METHODS
We tested the homogeneity, stability, and commutability of 5 minimally processed human serum pools according to the standard guidelines. The serum pools were assigned values as per the reference procedure of the United States Centers for Disease Control and were used to evaluate the trueness of results from 6 commercial measurement systems based on enzymatic methods: 3 glucose oxidase (GOD) and 3 hexokinase (HK) methods.
RESULTS
The prepared RMs were validated to be sufficiently homogenous, stable, and commutable with the patient samples. Method bias varied for different systems: GOD01, -0.17 to 2.88%; GOD02, 1.66 to 4.58%; GOD03, -0.17 to 3.14%; HK01, -3.48 to -0.85%; HK02, -3.83 to -0.11%, and HK03, -1.82 to -0.27%.
CONCLUSIONS
We observed that the prepared serum glucose RMs were qualified for trueness assessment. Most of the measurement systems met the minimal quality specifications.

Keyword

Glucose; Reference material; Commercial system; Bias

MeSH Terms

Blood Chemical Analysis/instrumentation/*standards
Blood Glucose/*analysis
Glucose Oxidase/metabolism
Hexokinase/metabolism
Humans
Reagent Kits, Diagnostic
Reference Standards
Regression Analysis

Figure

• 

  Fig. 1 The stability observation of the RMs for storage at -70℃. Abbreviation: RM, reference material.

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  Fig. 2 Commutability assessment of the RMs for the reference method and the commercial system by using the regression line (continuous line) and 95% prediction interval (dashed line). Black squares represent the RMs and gray circles represent the 40 patient samples. Abbreviations: GOD, glucose oxidase; HK, hexokinase.

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  Fig. 3 Mean values±2 SDs of the results from 3 laboratories with 6 commercial systems. The gray area represents the assigned value and its expanded uncertainty for the reference material.

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