Improving CardioCheck PA analytical performance: three-year study

Background: Cardiovascular prevention requires a diagnostic approach for population-based screening programmes aimed at early identification of modifiable risk factors. Dyslipidaemia, which is a major risk factor for cardiovascular disease, remains largely undiagnosed and undertreated. Point-of-care testing (POCT) provides immediate results for clinical decision-making, however, quality assessment is essential to ensure system performance requirements. CardioChek PA (CCPA), a portable whole blood analyser for rapid lipid measurement, has been on the market since 2002 but with limited evidence of performance levels. The aim of the study was to assess analytical performance issues of the device and possibly contribute to their solution. Methods: Over a 3-year period, we repeatedly evaluated CCPA accuracy, precision, and discrepancies between instruments and between test strip lots by comparison with laboratory method. At our initial evaluation, the CCPA analyser underestimated total cholesterol (bias 6.5%) and gave within-assay CVs above 6% for all lipid fractions. Our results solicited sequential improvements to the CCPA system by the manufacturer up to the performance level certified by the Cholesterol Reference Method Laboratory Network in 2013: total error 1.3% for total cholesterol and 3.1% for high density lipoprotein (HDL) cholesterol. Conclusions: POCT diagnostic tests need continuous quality management, including both quality control and quality assurance, to monitor the analytical process. A 3-year external quality surveillance provided information useful in improving POCT performance. As a result, the device is now adequate for use in screening programmes aimed at early detection of lipid disorders.