Terminological problems around "accuracy" and "uncertainty".

The consistent description and treatment of metrological data in laboratory medicine are hampered by the lack of a systematic, universally accepted nomenclature and by variations in the conceptual understanding of uncertainty. The differences between the classical approach to a result as consisting of a true value plus errors and the new approach of a measured corrected value with uncertainty based on a detailed uncertainty budget are discussed. The various definitions of some relevant concepts, including "accuracy", the new concept "trueness", and "precision", are contrasted, and proposed modification are presented.