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Don't repeat HbA1c testing sooner than the guideline interval when a recent result exists (every 3 years if normal; annually if stable prediabetes). Setting: a recent HbA1c result exists (normal within the last 3 years, or stable prediabetes within the last year) and a repeat is ordered sooner than the guideline interval without a change in clinical status or therapy Why: HbA1c reflects ~3 months of glycaemia and changes slowly; repeating it inside the guideline interval in stable patients cannot change management and adds cost. Consider instead: retrieve and act on the prior result; retest at the guideline interval or when clinical status or therapy changes Source: Society of General Internal Medicine (Choosing Wisely, US, 2017).
Don't repeat lipid panels sooner than the guideline interval in patients at goal or with a recent normal result. Setting: patient at lipid goal or with a recent normal lipid panel, without new cardiovascular events or a change in lipid-lowering therapy, re-tested sooner than the guideline interval Why: Lipid values are stable over months in unchanged patients; early repeats do not alter therapy and add cost. Consider instead: use the prior panel; repeat at guideline intervals (typically 4-12 weeks after a therapy change, then annually or less often when stable) Source: Society of General Internal Medicine (Choosing Wisely, US, 2017).