Does understanding metrological traceability in analytical measurement require going “back to basics”?

A measurement procedure If a sufficiently comprehensive description of the measurement is contained in a ‘measurement procedure’ (entry 2.6 in [1]) -which is a document containing a detailed description- it can serve the purpose of being a “reference” for realizing a quantity. In matters of “uncertainty,” any measured value obtained by such a procedure, can only be equipped by a statement of reproducibility (or repeatability) and robustness of its results, possibly increased by an evaluation of the limited amount of information about the measurand. A rather simple example of a measurement procedure, leading to an operationally defined measurand, is the measurement of “leachable Cd mass fraction” of a ceramic plate, i.e., the Cd content expressed in mmol/kg, of a specified acid solution having been in contact with a specified plate for a given time and a given temperature.