Il progetto pilota SIBioC di VEQ della misura dell'emoglobina glicata

Two fresh blood samples collected with EDTA were distributed by courier in December 2014 to 206 Italian laboratories asking for the determination of their HbA_1c concentrations. Target HbA_1c values were assigned by the IFCC reference measurement procedure based on HPLCcapillary electrophoresis. The results, collected from 193 laboratories using analytical systems mainly from five manufacturers (Bio-Rad Laboratories, A. Menarini Diagnostics, Roche Diagnostics, Sebia and Tosoh), showed a global variability (in terms of CV) of 5.3% and 3.8% at HbA_1c values of 37.4 mmol/mol (sample 1) and 62.0 mmol/mol (sample 2), respectively. Globally, 84% of the participants reported HbA_1c results within the total allowable error (TE) of 8.6% (sample 1) and 93% for sample 2. These percentages decreased to 70% and 77%, respectively, when using a goal for the allowable TE of 6.0% as criterion. Inter-laboratory CVs, calculated per group of methods, were between 3.3% and 5.0% and between 2.2% and 3.7% for sample 1 and 2, respectively. Tosoh users registered the smaller inter-laboratory CV in sample 1 and Sebia's in sample 2. With regard to trueness, all methods had a mean bias ≤2.8% respect to the target values, with the exception of Tosoh (bias of +6.1% and +5.8%, for samples 1 and 2, respectively).