PT - JOURNAL ARTICLE AU - A H Berg AU - D B Sacks TI - Haemoglobin A<sub>1c</sub> analysis in the management of patients with diabetes: from chaos to harmony AID - 10.1136/jcp.2007.049205 DP - 2008 Sep 01 TA - Journal of Clinical Pathology PG - 983--987 VI - 61 IP - 9 4099 - http://jcp.bmj.com/content/61/9/983.short 4100 - http://jcp.bmj.com/content/61/9/983.full SO - J Clin Pathol2008 Sep 01; 61 AB - Effective management of patients with diabetes mellitus requires accurate assessments of blood glucose control. The best characterised marker of long term glycaemic control is whole blood haemoglobin A1c (HbA1c). Published clinical trials have identified quantitative and direct relationships between the HbA1c concentration and risks of diabetic microvascular complications. However, in order to practice evidence-based medicine, assays used to measure patient samples should ideally produce values comparable to the assays used in these trials. Numerous assays using chromatographic and immunological detection methods are used around the world. This paper briefly reviews the scientific evolution of HbA1c and its analysis, discusses the reasons why HbA1c assay standardisation is a challenge, describes the approaches that have been adopted to harmonise HbA1c assays, and addresses the current initiatives to standardise HbA1c globally. These efforts have established HbA1c as an essential component in the management of patients with diabetes mellitus and are likely to lead to the use of HbA1c in the screening/diagnosis of diabetes.