title: Evaluation of two HbA1c point-of-care analyzers.
abstract: BACKGROUND
  Measurement of HbA1c is the most important parameter to assess glycemic control in diabetic patients. Different point-of-care devices for HbA1c are available. The aim of this study was to evaluate two point-of-care testing (POCT) analyzers (DCA Vantage from Siemens and Afinion from Axis-Shield). We studied the bias and precision as well as interference from carbamylated hemoglobin.
  
  
  METHODS
  Bias of the POCT analyzers was obtained by measuring 53 blood samples from diabetic patients with a wide range of HbA1c, 4%-14% (20-130 mmol/mol), and comparing the results with those obtained by the laboratory method: HPLC HA 8160 Menarini. Precision was performed by 20 successive determinations of two samples with low 4.2% (22 mmol/mol) and high 9.5% (80 mmol/mol) HbA1c values. The possible interference from carbamylated hemoglobin was studied using 25 samples from patients with chronic renal failure.
  
  
  RESULTS
  The means of the differences between measurements performed by each POCT analyzer and the laboratory method (95% confidence interval) were: 0.28% (p<0.005) (0.10-0.44) for DCA and 0.27% (p<0.001) (0.19-0.35) for Afinion. Correlation coefficients were: r=0.973 for DCA, and r=0.991 for Afinion. The mean bias observed by using samples from chronic renal failure patients were 0.2 (range -0.4, 0.4) for DCA and 0.2 (-0.2, 0.5) for Afinion. Imprecision results were: CV=3.1% (high HbA1c) and 2.97% (low HbA1c) for DCA, CV=1.95% (high HbA1c) and 2.66% (low HbA1c) for Afinion.
  
  
  CONCLUSIONS
  Both POCT analyzers for HbA1c show good correlation with the laboratory method and acceptable precision.
authors.affiliation: Clinical Biochemistry Department, Virgen Macarena University Hospital, Seville, Spain.
authors.forename: Catalina
authors.initials: C
authors.lastname: Sánchez-Mora
authors.forename: Manuel
authors.initials: M
authors.lastname: S Rodríguez-Oliva
authors.forename: Patricia
authors.initials: P
authors.lastname: Fernández-Riejos
authors.forename: Joaquín
authors.initials: J
authors.lastname: Mateo
authors.forename: Juan
authors.initials: J
authors.lastname: Polo-Padillo
authors.forename: Raimundo
authors.initials: R
authors.lastname: Goberna
authors.forename: Víctor
authors.initials: V
authors.lastname: Sánchez-Margalet
mesh_terms: D015982:Bias; D001774:Blood Chemical Analysis / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007753:Laboratories / Q000592:standards; D019095:Point-of-Care Systems / Q000592:standards; D012016:Reference Values; D015203:Reproducibility of Results
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human