Arbitrary substance concentration (arb.subst.c.)

Abbreviation

Arb.subst.c.

Definition in words

Arbitrary amount-of-substance of component B divided by volume of system 1

Definition by equation

Note: kprocedure is a constant defined by the measurement procedure (there is an approximately proportionality to a kind-of-quantity from the International System of Quantities).

Ratio scale
  • Value sets are positive numerical values
  • Numerical values from 0-∞
  • Algebraic operations are allowed
  • Possible comparison of values (a=nb; a≠nb)

Unit

International unit (IU) or procedure defined unit (p.d.u.) (non-SI units)

Special rule(s) in the NPU syntax

“Procedure” is stated in the specification to the kind-of-property in the NPU definition.

“Procedure” indicates that the measurement procedure must be stated somewhere else than the NPU code and there may be difficulties in comparing values for the same NPU code.

If the unit is an International Unit (IU), an international certified reference material (e.g. WHO reference material) is specified in the specification to the kind-of-property.

If there exist no international certified reference material, the laboratory can specify the unit at the placeholder, procedure defined unit.

Reference

Ferard G, Dybkaer R, Fuentes-Arderiu X. Compendium of Terminology and Nomenclature of Properties in Clinical Laboratory Sciences : Recommendations 2016. 1 ed: Royal Society of Chemistry; 2016. 182 p. doi:10.1039/9781782622451.

Laboratory field

Examples

Allergology

Example 1
Generic abbreviated form NPU56406 P—Immunoglobulin E; arb.subst.c.(IS 11/234; proc.) = 10 × 103 IU/L
Full form with a result NPU56406 Plasma—Immunoglobulin E; arbitrary substance concentration(IS 11/234; procedure) = 10 × 103 International Unit per litre
Abbreviated form with a result NPU56406 P—Immunoglobulin E; arb.subst.c.(IS 11/234; proc.) = 10 × 103 IU/L
Written expression The arbitrary substance concentration of Immunoglobulin E in Mr. Smih’s plasma is [10] × 103 IU/L. The measurement is performed by a procedure defined by the laboratory. “IU” and its magnitude is defined by the Certified Reference Material, IS 11/234 from WHO.
Equation

Clinical Chemistry

Example 2
Generic abbreviated form NPU58412 P—Choriogonadotropin+beta-chain; arb.subst.c.(proc.) = ? (p.d.u.)
Full form with a result NPU58412 Plasma—Choriogonadotropin+beta-chain; arbitrary substance concentration(procedure) = 24 arbitrary unit per litre
Abbreviated form with a result NPU58412 P—Choriogonadotropin+beta-chain; arb.subst.c.(proc.) = 24 arbitrary unit/L
Written expression The arbitrary substance concentration of Choriogonadotropin+beta-chain in Mrs. Smith’s plasma is [24] arbitrary unit/L. The measurement is performed by a procedure defined by the laboratory.
Equation
Notes
“Arbitrary unit” was chosen by a local laboratory as a proprietary measurement unit. and not an accepted international unit.

Clinical Phamarcology

Example 3
Generic abbreviated form NPU57089 P—Rituximab antibody; arb.subst.c.(proc.) = ? (p.d.u.)
Full form with a result NPU57089 Plasma—Rituximab antibody; arbitrary substance concentration(procedure) = 2 arbitrary unit per litre
Abbreviated form with a result NPU57089 P—Rituximab antibody; arb.subst.c.(proc.) = 2 arbitrary unit/L
Written expression The arbitrary substance concentration of Rituximab antibody in Mr. Smith’s plasma is [2] arbitrary unit/L. The measurement is performed by a procedure defined by the laboratory.
Equation
Notes “Arbitrary unit” was chosen by a local laboratory as a proprietary measurement unit. and not an accepted international unit.

Clinical Immunology and Blood bank

Example 4
Generic abbreviated form NPU26643 P—DNA topoisomerase 1 antibody(IgG); arb.subst.c.(proc.) = ? (p.d.u.)
Full form with a result NPU26643 Plasma—DNA topoisomerase 1 antibody(Immunoglobulin G); arbitrary substance concentration(procedure) = 37 ELISA unit/L
Abbreviated form with a result NPU26643 P—DNA topoisomerase 1 antibody(IgG); arb.subst.c.(proc.) = 37 ELISA unit perlitre
Written expression The arbitrary substance concentration of DNA topoisomerase 1 antibody(Immunoglobulin G) in Mr. Smith’s plasma is [37] ELISA unit/L. The measurement is performed by a procedure defined by the laboratory.
Equation
Notes “ELISA unit” was chosen by a local laboratory as a proprietary measurement unit. and not an accepted international unit.

Clinical Microbiology

Example 5
Generic abbreviated form NPU29472 P—Tick-borne encephalitisvirus antibody(IgG); arb.subst.c.(proc.) = ? (p.d.u.)
Full form with a result NPU29472 Plasma—Tick-borne encephalitisvirus antibody(Immunoglobulin G); arbitrary substance concentration(procedure) = 125 Multiplate unit/L
Abbreviated form with a result NPU29472 P—Tick-borne encephalitisvirus antibody(IgG); arb.subst.c.(proc.) = 125 Multiplate unit/L
Written expression The arbitrary substance concentration of Tick-borne encephalitisvirus antibody(Immunoglobulin G) in Mr. Smith’s plasma is [125] Multiplate unit/L. The measurement is performed by a procedure defined by the laboratory.
Equation
Notes “Multiplate unit”  was chosen by a local laboratory as a proprietary measurement unit. and not an accepted international unit.

Reproduction and Fertility

Example 6
Generic abbreviated form NPU01574 SemP—Chorionic Gonadotropin; arb.subst.c.(IS 75/537; proc.) = ? IU/L
Full form with a result NPU01574 Seminal Plasma—Chorionic Gonadotropin; arbitrary substance concentration(IS 75/537; procedure) = 6 International Unit per litre
Abbreviated form with a result NPU01574 SemP—Chorionic Gonadotropin; arb.subst.c.(IS 75/537; proc.) = 6 IU/L
Written expression The arbitrary substance concentration of Chorionic Gonadotropin in Mr. Smith’s seminal plasma is [6] IU/L. The measurement is performed by a procedure defined by the laboratory. “IU” and its magnitude is defined by the Certified Reference Material, IS 75/537 from WHO.
Equation

Thrombosis and Haemostasis

Example 7
Generic abbreviated form NPU28289 P—Fibrin D-dimer; arb.subst.c.(proc.) = ? (p.d.u.)
Full form with a result NPU28289 Plasma—Fibrin D-dimer; arbitrary substance concentration(procedure) = 5 FEU
Abbreviated form with a result NPU28289 P—Fibrin D-dimer; arb.subst.c.(proc.) =5 FEU
Written expression The arbitrary substance concentration of Fibrin D-dimer in Mr. Smith’s plasma is [5] FEU. The measurement is performed by a procedure defined by the laboratory.
Equation
Notes “FEU”  was chosen by a local laboratory as a proprietary measurement unit. and not an accepted international unit.

Reference

NPU database, https://www.ifcc.org/ifcc-scientific-division/sd-committees/c-npu/npusearch/ and http://www.labterm.dk/default.aspx
  • Kind-of-property

    • Nominal kind-of-property

    • Kind-of-quantity

      • Ordinal kind-of-quantity

      • Unitary kind-of-quantity

        • Rational unitary kind-of-quantity

            • Arbitrary substance concentration

Reference

  • Dybkaer R. Concept system on ‘quantity’: formation and terminology. Accredit Qual Assur. 2013;18(3):253-60.
  • Dybkaer R. ISO terminological analysis of the VIM3 concepts ‘quantity’ and ‘kind-of-quantity’. Metrologia. 2010;47(3):127-34.
Date Term Note
1996-01-01 Arbitrary substance concentration Term established