@Helene Tuft Stavnes : “P—Apolipoprotein B/Apolipoprotein A1; subst.ratio =” is created as “Substance ratio of apolipoprotein A-I and apolipoprotein B in plasma in (observable entity)”. Not sure that "apolipoprotein A-I and apolipoprotein B "is right: should be something like divided by/between?
The SNOMED attribute 704325000 |Relative to (attribute)| (meaning relative to component) and possibly 719715003 |Relative to part of (attribute)| (meaning relative to, inheres in, the related system in NPU-speak) can be used for ratios.
Need examples to understand the difference. 704325000 | Relative to (attribute) | is explained as “This attribute is used to specify the denominator of a relational property type, such as a ratio or proportion.” (note that NPU distinguish between ratios (possible values -∞ – +∞) and proportions (possible values 0–1))
719715003 | Relative to part of (attribute) | is explained by “This attribute is used to specify the denominator of a relative relational property type, such as a ratio of ratios”. What is a relative relational property type? Corresponding to something we term index in NPU??
This was a figure drawn some years ago. Any kind of property such as ratio or relative substance concentration can make use of these attributes, but the meaning would be constrained by the kind of property.
Cf. 491971010000101 |Mass ratio of apolipoprotein A-I to apolipoprotein B in serum or plasma at point in time (observable entity)|