Abstract
Since the discovery of the association between glycated haemoglobin (HbA1c) and glucose control in 1968,1 HbA1c has been adopted globally and continues to be the primary marker for overall glycaemic control due to its convenience, wide availability and evidence base for association with diabetes complications.2-4 This measure is dependent on assay performance, blood glucose levels, the glycation process itself and the lifespan of red blood cells (RBCs).5 With the widespread adoption of continuous glucose monitoring (CGM), it is becoming clear that glucose metrics and HbA1c may be discordant.