Establishing, evaluating and monitoring analytical quality in the traceability era

Poor analytical quality may be the bane of medical use of laboratory tests, and the fight against excessive analytical variability presents a daily struggle. Laboratories should prioritize the perspectives and needs of their customers (the patients and healthcare personnel). Among them, comparability of results from the same patient sample when measured by different laboratories using different in vitro diagnostic (IVD) medical devices is a logical priority to avoid result misinterpretation and potential patient harm. Harmonization (standardization) of laboratory measurements can be achieved by establishing metrological traceability of the results on clinical samples to stated higher-order references and providing an estimate of the uncertainty of measurement (MU). This estimate should be based on an MU budget including all known MU contributions generated by the employed calibration hierarchy, which in turn should be validated against fit-for-purpose maximum allowable MU derived according to internationally recommended models. In this report, we review the available strategies for establishing, evaluating, and monitoring analytical quality, drawing on three decades experience in the field. We discuss the most important aspects that may influence obtaining and maintaining analytical standardization in laboratory medicine, and offer practical solutions aimed at educating all stakeholders for the achievement of harmonized laboratory results. To fully implement the recommended approaches, all involved parties-i.e. reference providers, IVD manufacturers, medical laboratories, and External Quality Assessment organizers-must agree on their importance and enhance their specific knowledge.