Setting quality specifications for the future with newer approaches to defining uncertainty in laboratory medicine

When describing the performance of procedures and the reliability of their results, ISO terminology should be used. Results should be universally comparable and this requires metrological traceability. The concomitant uncertainty (inversely) indicating reliability should be obtained in a universal and transparent fashion, and should be combinable. Therefore, the approach of the "Guide to the expression of uncertainty in measurement", leading to a result without known bias and a combined standard uncertainty, has advantages over the allowable total error concept, incorporating procedural bias.