Monitoring glycaemic control: is there evidence for appropriate use of routine measurement of glycated haemoglobin?

Background: Regardless of the available recommendations to perform glycated haemoglobin testing at a 2- to 3-month frequency, there is increasing evidence of an inappropriate laboratory use of this test in clinical practice. Methods: Data from our Laboratory Information System were analysed for glycated haemoglobin test orders over a 3-year period using Microsoft® Excel to calculate the order intervals and the test frequency for each patient. To assess the appropriateness of repeat testing, only data for patients who had at least two separate glycated haemoglobin test results were included in the analysis. Inappropriate test orders were defined as any order for a given patient taking place within a 29- or 89-day period following the previous order. Results: The results of our investigation demonstrate that inappropriate laboratory utilisation of this test is commonplace (26% of total repeat orders within 90 days), especially for inpatients (63.7% of inpatient repeat orders in less than...