Evaluation of HbA1c on COBAS INTEGRA 800 Closed Tube System Compared with Variant II Turbo / 임상검사와정도관리

BACKGROUND: We evaluated the HbA1c assay on COBAS INTEGRA 800 Closed Tube System (Roche Diagnostics, USA). METHODS: Precision was determined following Clinical and Laboratory Standards Institute (CLSI) EP5-A2 using the Lyphochek Diabetes Control (Bio-Rad Laboratories, Canada). Two levels of QC materials were assayed in duplicates at two separate times per day for 20 days. The within-run, between-run and between-day precisions were evaluated. We compared the HbA1c of COBAS INTEGRA 800 Closed tube system using Tina quant Hemoglobin A1c Gen.2 (Roche Diagnostics, Germany) reagent with Variant II Turbo (Bio-Rad Laboratories, USA). Bias was determined following CLSI EP9-A2. RESULT: The HbA1c assay on COBAS INTEGRA 800 Closed Tube System showed excellent precision performance: at a level of 5.9%, total, between run, and between day CVs were 1.8%, 0.5%, and 1.6%, respectively. At a level of 9.6%, total, between run, and between day CVs were 1.4%, 0.3%, and 1.1%, respectively. The assay correlated well with the Variant II Turbo (y=0.9x+0.53, r2=0.9857). Mean bias against Variant II Turbo was -0.2%. Compared with Variant II Turbo, the estimate of the predicted bias at a given medical decision level (HbA1c at 6% and 9%) was -0.1% and -0.31%, respectively. CONCLUSIONS: The COBAS INTEGRA 800 Closed Tube System HbA1C assay was precise and equivalent to Variant II Turbo.

Comparison of HbA(1c) Analyzers: D-10, Variant II Turbo, Cobas Integra 800, and Afinion AS100 / 대한진단검사의학회지

BACKGROUND: The purpose of this study was to evaluate the performance and agreement among HbA(1c) values measured using selected analyzers certified by the National Glycohemoglobin Standardization Program (NGSP) and standardized by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). METHODS: HbA(1c) determined using D-10 (Bio-Rad, USA), Variant II Turbo (Turbo; Bio-Rad, USA), Cobas Integra 800 (Integra; Roche, Switzerland) and Afinion AS100 (Afinion; Axis-Shield, Norway) were compared with each other. Precision and method comparisons with Deming regression were evaluated according to CLSI recommendations. We also compared the HbA(1c) values obtained with each analyzer using either IFCC or NGSP methods by correlation analysis and kappa statistics. RESULTS: The repeatability and method/device precisions of D-10 and Afinion were acceptable. The correlation coefficients of HbA(1c) were 0.986 for D-10 vs. Afinion, 0.997 for D-10 vs. Turbo, 0.988 for D-10 vs. Integra, and 0.991 for Integra vs. Afinion. The average biases of HbA(1c) Afinion (IFCC) and HbA(1c) Integra (IFCC) against HbA(1c) D-10 (NGSP) were -1.90% and -1.79%, respectively. Kappa agreement statistics for the three diabetic control group HbA(1c) values of "less than 6.5%," "6.5%-7.5%," and "greater than 7.5%" for D-10 vs. Turbo, D-10 vs. Integra, and D-10 vs. Afinion were 0.872, 0.836, and 0.833, respectively. CONCLUSIONS: The strong correlations and good clinical agreements of HbA(1c) between each analyzer expressed in terms of either NGSP or IFCC-derived NGSP indicate that these analyzers can be used interchangeably.

Evaluation of Hemoglobin A1c on the Cobas Integra 800 Immunoassay and Tosoh HLC-723 G8 HPLC Analyzer / 임상검사와정도관리

BACKGROUND: Hemoglobin A1c (HbA1c) is a good marker for the monitoring of glycemic control in patients with diabetes mellitus and various methods are used for determination of HbA1c. We evaluated the analytical performance of ion-exchange high-performance liquid chromatography system, standard mode (G8 SM) and variant mode (G8 VM) of Tosoh HLC-723 G8 (Tosoh Corporation, Japan) and Cobas Integra 800 (Roche Diagnostics, Germany) using new reagent (Tina-quant Hemoglobin A1c Gen.2, Roche Diagnostics) for immunoassay. METHODS: G8 SM, G8 VM, and Cobas Integra 800 were evaluated for linearity, precision, comparison of method, and speed. Variant II Turbo (Bio-Rad Laboratories, USA) was used for comparison test for above three analyzers. RESULTS: Three instruments showed within-run precision (CVs) of 0.52-1.12% in low level and 0.39-0.90% in high level control material. Total run precision (CVs) were in 0.95-1.26% in low level and 0.60-0.94% in high level control material. The linearity was good for the range of 4-15% and comparison with Variant II turbo was excellent with 0.9878-0.9977 of correlation coefficient. Analytical speed was 2 min/1 min in G8 SM, 3.5 min/1.5 min in G8 VM, and 14.7 min/18 sec in Cobas Integra 800, respectively. CONCLUSIONS: HLC-723 G8 SM and VM, and Cobas Integra 800 were showed excellent linearity, precision, and comparison with other instrument. We should consider the characteristics including analytical method and speed in each instrument when clinical laboratory is planning to introduce different equipment for HbA1c determination.