title: Biological variability of glycated hemoglobin.
abstract: BACKGROUND
  The measurement of glycated hemoglobin (HbA(1c)) has a pivotal role in monitoring glycemic state in diabetic patients. Furthermore, the American Diabetes Association has recently recommended the use of HbA(1c) for diabetes diagnosis, but a clear definition of the clinically allowable measurement error is still lacking. Information on biological variability of the analyte can be used to achieve this goal.
  
  
  METHODS
  We systematically reviewed the published studies on the biological variation of HbA(1c) to check consistency of available data in order to accurately define analytical goals.
  
  
  RESULTS
  The nine recruited studies were limited by choice of analytic methodology, population selection, protocol application and statistical analyses.
  
  
  CONCLUSIONS
  There is an urgent need to determine biological variability of HbA(1c) using a specific and traceable assay, appropriate protocol and appropriate statistical evaluation of data.
authors.affiliation: Centro Interdipartimentale per la Riferibilità Metrologica in Medicina di Laboratorio (CIRME), Università degli Studi, Milano, Italy. federica.braga@studenti.unimi.it
authors.forename: Federica
authors.initials: F
authors.lastname: Braga
authors.forename: Alberto
authors.initials: A
authors.lastname: Dolci
authors.forename: Andrea
authors.initials: A
authors.lastname: Mosca
authors.forename: Mauro
authors.initials: M
authors.lastname: Panteghini
mesh_terms: D003920:Diabetes Mellitus / Q000097:blood; D015340:Epidemiologic Research Design; D006442:Glycated Hemoglobin / Q000032:analysis* / Q000592:standards; D006801:Humans; D015588:Observer Variation; D015203:Reproducibility of Results; D012107:Research Design / Q000592:standards
chemical_list: D006442:Glycated Hemoglobin