Accuracy of a Point-of-Care Hemoglobin A1c Assay

David M Nathan1,2, Amanda Griffin1, Francesca M Perez3

  • 1Diabetes Center, Massachusetts General Hospital, Boston, MA, USA.

Point-of-care test (POCT) HbA1c assays provide rapidly available results for clinical decision-making. Accuracy and precision must be established. Venous blood samples from 300 patients were assayed for HbA1c by a laboratory technician ("laboratory assessment") with the POCT Alere Afinion™ assay and a laboratory (Premier AffinityTM) assay. POCT results from 402 patients' fingerstick samples assayed by nine nontechnician staff ("clinical assessment") were compared with the laboratory assay. The laboratory assessment showed tight correlation (r2 = .977, P < .001) between the assays. Mean absolute and relative differences were 0.01 percentage points and 2.1%, respectively. CVs for the POCT and laboratory assays were <2% and <1%, respectively. The clinical assessment also showed a tight correlation between the assays (r2 = .978, P < .001), with mean absolute and relative differences of 0.2 percentage points and 3.41%, respectively. CV for the POCT assay was <2%. The POCT performed acceptably compared to the laboratory assay under realistic clinical conditions.

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