Thank you Heather (belatedly) I had misunderstood.
So the proposal for a 10-point, single-digit scale looks good. Is that intended to replace, or would it co-exist with the 5-point text scale suggested previously to align with 5 x SCT codes, with the intermediate values intended to be interpolated?
If so, I’d suggest that “interpolation” is troublesome for ordinal values, and we should craft text statements for the intermediate ranks too.
I think there is a problem with ordinal ranks being marked by number, as if integers: they are not rational numbers so arithmetic is not valid. For instance, a rank of 2 is not half as bad as a rank of 4, nor is 3 halfway between them.
We “know” this, but the use of numbers traps people into thinking like this.
Textbooks state that ordinal numbers always need statistical processing, not arithmetic.
The Statistical Evaluation of Medical Tests for Classification and Predicti…
I have researched this cognitive risk e.g. see The ABC of cardinal and ordinal number representations: Trends in Cognitive Sciences (cell.com)
and real-world misuse of ordinal numbers e.g. at Use of the Palliative Performance Scale (PPS) … .
I suggest that other serial symbols such as alphabetic should be used: if the above 3 ranks were denoted as a/b/c there would be no quantitative inference of meaning from the different symbols.
However this does not seem compatible with the discussion at Clinical scales - ordinal or coded text? - Clinical - openEHR . Sorry to say further confused by Text, descriptions and comments for value set items - mandatory or optional? - Clinical - openEHR
Is it that this is not our problem, but that of all those clinical scale authors that have (mis)used numbers as ordinals, which openEHR can only seek to represent. Or should openEHR at least alert developers that ordinal numbers are trouble?
As a beginner in openEHR please excuse if this is off-point , but would be grateful for your advice and corrections