EKF Diagnostics announces that in a newly-published paper  its Quo-Test point-of-care (POC) hemoglobin A1c (HbA1c) analyser has again been confirmed to meet International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) performance criteria.
Using sigma-metrics data modelling, scientists from the European Reference Laboratory for Glycohemoglobin demonstrated that Quo-Test easily met IFCC accepted quality targets of >2 sigma at 10% total allowable error (TAE) at 48 mmol/mol HbA1c. This is essential for the effective monitoring of glycemic control in diabetes patients.
Under strict evaluation conditions, Quo-Test was not only shown to perform extremely well against routine laboratory analysers, certified as secondary reference measurement procedures (SRMPs), but also when compared to six other POC HbA1c analysers.
The authors explained that in the laboratory, sigma-metrics is a quality management strategy that provides a universal benchmark for analytical performance - effectively placing all analysers on a level playing field.
Using sigma-metrics, analytical characteristics (bias and imprecision) are placed in the form of TAE within a framework of clinical requirements. An IFCC Task Force in 2015 advocated the use of sigma-metrics quality targets for HbA1c to standardisze analytical quality at a global level .
This latest study  follows the release of critical evaluation data by the European Reference Laboratory for Glycohemoglobin published in a white paper in 2016 , which also demonstrated Quo-Test’s strong performance.
In the white paper Quo-Test’s performance in sigma-metrics was very good. Sigma was shown to be >2 at 48mmol/mol and at an HbA1c value of 75 mmol/mol >4. Examining the CVs of all duplicates, one lot number even had a sigma of >6; this is a class-leading level of performance.
Notably, within the 2016 evaluation study, the boronate affinity fluorescence quenching technology employed by Quo-Test was demonstrated to maintain results consistency due to its ability to minimize the effects of hemoglobin variants. This compared well with laboratory-based HPLC systems. Quo-Test showed no interference of the common Hb-variants HbAS, HbAC, HbAD, HbAE, HBAJ, elevated A2 and HbF<8.6%.
CE-marked for the monitoring of HbA1c in diabetes patients, Quo-Test is specifically designed for use in a POC setting, such as diabetes clinics and doctors’ surgeries. It is fully automated, measuring HbA1c from a 4 µL sample taken from a finger prick or venous whole blood. Results are available in four minutes within a measuring range of 4-15% A1c DCCT, and precision performance with a CV of 2.2% at 6.6% DCCT has been demonstrated .
Lenters-Westra, E. & English, E. Understanding the use of sigma metrics in hemoglobin A1c analysis. Clin Lab Med 2017;37: 57-71.
Weykamp, C., John, G., Gillery P. et al. on behalf of the IFCC Task Force on Implementation of HbA1c Standardization. Investigation of 2 models to set and evaluate quality targets for HbA1c: biological variation and sigma-metrics. Clin Chem 2015;61(5): 752-9.
Lenters-Westra, E. An evaluation of the Quo-Test performance against NGSP and sigma-metrics. 2016 White Paper available for download HERE.