[Working group of the French Society of Clinical Biology (SFBC) and the National College of Hospital Biochemistry (CNBH) on the evaluation of laboratory blood glucose measurement].

Blood glucose measurement remains a cornerstone in clinical biochemistry, playing a critical role in the diagnosis and monitoring of diabetes mellitus, including gestational diabetes. In France, the diagnosis of diabetes continues to rely exclusively on laboratory-based plasma or serum glucose measurement, as HbA1c is not currently accepted as a diagnostic marker. Nonetheless, several pre-analytical factors may compromise glucose measurement, particularly in vitro glycolysis, which can significantly reduce measured concentrations if not adequately controlled. In 2025, the French Society of Clinical Biology (SFBC) and the National College of Hospital Biochemistry (CNBH) established a working group with the following objectives: (i) to assess current laboratory practices for glucose measurement, and (ii) to review and update the available scientific literature to develop evidence-based recommendations. To achieve these goals, three thematic subgroups were created to conduct: 1) a literature review: focusing on pre-analytical variables, the analytical performance of blood collection tubes, the clinical indications for laboratory glucose testing, and the definition of context-specific reference values; 2) a field survey: designed to capture current practices among clinical biochemists in France and other French-speaking countries; 3) research studies involving on-site experimental trials to directly compare different methodological approaches and pre-analytical strategies. This initiative aims to provide a comprehensive overview of current practices, identify gaps in knowledge, and ultimately support the development of harmonized national recommendations for glucose measurement particularly in the diagnostic and clinical management of diabetes.