Continuous glucose monitoring and metrics for clinical trials: an international consensus statement.

Randomised controlled trials and other prospective clinical studies for novel medical interventions in people with diabetes have traditionally reported HbA as the measure of average blood glucose levels for the 3 months preceding the HbA test date. The use of this measure highlights the long-established correlation between HbA and relative risk of diabetes complications; the change in the measure, before and after the therapeutic intervention, is used by regulators for the approval of medications for diabetes. However, with the increasing use of continuous glucose monitoring (CGM) in clinical practice, prospective clinical studies are also increasingly using CGM devices to collect data and evaluate glucose profiles among study participants, complementing HbA findings, and further assess the effects of therapeutic interventions on HbA.