[Can a laboratory investigation be called anything? "The NPU system" sorts out the concepts and gives systematic stringency].

When communicating results from laboratory investigations from the laboratory to the requesters and further between different information systems, it is important that the value as well as the unique identity and name of the laboratory investigation are correctly cited. A committee under the International Federation for Clinical Chemistry and Laboratory Medicine (IFCC) and International Union for Pure and Applied Chemistry (IUPAC) has developed a systematic nomenclature for the correct classification of laboratory investigations. Each generic laboratory investigation is provided with a unique NPU code.