NPU Terminology

Frequently Asked Questions

This page offers answers to most of your questions.

What is NPU laboratory terminology?

The NPU terminology is a coding system and terminology for identification and communication of examination results from clinical laboratories in the health area. It identifies types of result values, for use in reporting laboratory results. The definitions have a uniform structure and use a referenced vocabulary.

The NPU terminology covers many fields of laboratory medicine:

  • Clinical allergology
  • Clinical chemistry
  • Clinical immunology and blood banking
  • Clinical microbiology
  • Clinical pharmacology
  • Molecular biology and genetics
  • Reproduction and fertility
  • Thrombosis and hemostasis
  • Toxicology

What is NOT included in laboratory terminology?

The NPU terminology does not cover information about:

  • The sample material (such as heparin plasma, EDTA plasma or serum) and how the sample material has been stored before measurement.
  • The sampling site, which is also very important information, especially within the field of microbiology.
  • The measurement method, which is sometimes necessary to consider when a result is interpreted
  • The quality of the result value

Who owns laboratory terminology?

The ownership and intellectual property rights of NPU terminology are shared between the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) ( and the International Union of Pure and Applied Chemistry (IUPAC) (

Who owns and operates the NPU database?

The NPU database is owned and operated by the Danish National eHealth Authority ( The database is available in English and Danish and may be translated, with permission, into other languages. The database is updated monthly. The latest English version can be accessed here.

Who is responsible for governance of NPU terminology?

The NPU terminology is overseen by a Steering Committee.

Who is responsible for the ongoing development of NPU terminology?

The ongoing development of NPU terminology is achieved through a joint IFCC:IUPAC committee. This is a Committee of the Scientific Division of IFCC (C-NPU) and a Sub-Committee of IUPAC Division VII Chemistry and Human Health (SC-NPU).

Who may use NPU terminology?

The NPU terminology is freely accessible to any individual to aid understanding of what is measured in laboratory medicine. Adoption of NPU terminology on behalf of a group of users (e.g. through National Release Centres, private laboratory networks or diagnostics companies) is possible by agreement with the Steering Committee.

How international is NPU terminology?

Pilot projects have demonstrated that NPU terminology may be aligned with the SNOMED CT system. This is the most comprehensive and precise clinical health terminology product in the world, which is supported by many national governments ( The NPU Steering Committee is in communication with the International Health Terminology Standards Development Organisation (IHTSDO) to strengthen this relationship.

Why isn’t there a NPU code/definition for Serum-Potassium? (or any other properties of serum)?

The NPU terminology describes properties of the patient (or a part of the patient). Serum is not considered a part of a patient, it is a product that appears in a test tube after sample collection. Investigations performed on serum samples aim at estimating conditions in the patient’s plasma, at the moment the sample was collected. For that reason, the NPU terminology describes all investigations performed on serum samples as properties of plasma.