Substance ratio (subst.ratio) - Dynamic NPU Manual

Substance ratio (subst.ratio)


Mole ratio, amount-of-substance ratio



Definition in words

The amount-of-substance of component F divided by amount-of-substance of component G in system 1

Note 1: Component F ≠ Component G (≠ = “not equal to”)

Note 2: Component F ∉ Component G (∉ = “is not an element of”)

Note 3: The quotient of mass of component F and mass of component G is denoted “mass ratio of component B”

Definition by equation

Systematic terms

Substance ratio of component B in system 1

Result type

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


10-6, 10-3, 1 (one), 103, 106, etc.

Unit, one (1) is omitted in the NPU syntax


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.

Laboratory field


Clinical Chemistry

Example 1
Generic abbreviated
NPU04146 P—Cholesterol+ester, in LDL/Cholesterol+ester, in HDL; subst.ratio = ?
Full result NPU04146 Plasma—Cholesterol+ester, in LDL/Cholesterol+ester, in HDL; substance ratio = 8 x one
Abbreviated result NPU04146 P—Cholesterol+ester, in LDL/Cholesterol+ester, in HDL; subst.ratio = 8
Written expression The substance ratio of Cholesterol+ester, in LDL/Cholesterol+ester, in HDL in Mr. Smith’s plasma is [8].

Clinical Pharmacology

Example 2
Generic abbreviated
NPU54631 Ercs(B)—Methotrexate polyglutamate/Haemoglobin(Fe); subst.ratio = ? × 10-6
Full result NPU54631 Erythrocytes(Blood)—Methotrexate polyglutamate/Haemoglobin(Fe); substance ratio = 3.8 × 10-6
Abbreviated result NPU54631 Ercs(B)—Methotrexate polyglutamate/Haemoglobin(Fe); subst.ratio = 3.8 × 10-6
Written expression The substance ratio of Methotrexate polyglutamate/Haemoglobin(Fe) in erythrocytes from Mr. Smith’s blood is [3.8] × 10-6.

Molecular Biology and Genetics

Example 3
Generic abbreviated
NPU27488 U—Succinyladenosine/Creatininium; subst.ratio = ? × 10-3
Full result NPU27488 Urine—Succinyladenosine/Creatininium; substance ratio = 30 × 10-3
Abbreviated result NPU27488 U—Succinyladenosine/Creatininium; subst.ratio = 30 × 10-3
Written expression The substance ratio of Succinyladenosine/Creatininium in Mr. Smith’s urine is [30] × 10-3.

Thrombosis and Haemostasis

Example 4
Generic abbreviated
NPU29007 P—Fibrinogen; subst.ratio(coag./imm.; proc.) = ?
Full result NPU29007 Plasma—Fibrinogen; substance ratio(coagulation/immunological; procedure) = 0.86 × one
Abbreviated result NPU29007 P—Fibrinogen; subst.ratio(coag./imm.; proc.) = 0.86
Written expression The substance ratio of Fibrinogen(coagulation)/Fibrinogen(immunological) in Mr. Smith’s plasma is [0.86].The measurement is performed according to a procedure defined by the laboratory. The calculation was performed by division of the quantity of fibrinogen measured by a coagulation procedure divided by the quantity of fibrinogen measured by a immunological procedure.


  NPU database, and
  • Kind-of-property

    • Nominal kind-of-property

    • Kind-of-quantity

      • Unitary kind-of-quantity

        • Rational unitary kind-of-quantity


  • 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 Substance concentration Term established