this has clearly happened because the designers of the scale did not have the term 'very very slight' in the beginning, but unfortunately they had already chosen contiguous integers. I have to say, this scale looks quite subjective. I would be amazed to discover that a) the middle terms were being used in the same way across all users or that b) the outcomes would be any worse if a 3 or 5 item scale was used instead. But I am not a doctor, so ignore that comment ;-)
Practically speaking, I guess we are in the realm of having to create an ordinal kind of concept to deal with scales with retro-fitted non-integer items. A pragmatic approach might be to add a DV_ORDINAL variant called something like DV_SCALE_VALUE which is the same model as DV_ORDINAL but with the value of Real rather than Integer type. - thomas beale On 20/04/2010 12:35, Ian McNicoll wrote: > > Assessment scales provide a rich seam of frustration for developers, > with their seemingly limitless capacity for arbitrary scales and > quantities. > > Here is a current example about which I have been asked for advice - > the Borgscale (http://www.ac6v.com/karlaz2.htm). > > It is a scale from 0-10, so would be ideal to express as a DV_ORDINAL > but includes 0.5 which makes this impossible. > > There are a number of workarounds but is there a case for adding some > form of Coded Quantity datatype to openEHR? The primary problem is in > representing such constraints in archetypes but there might be some > value in simplifying integration from Snomed coded findings. > > *SCALE* > > > > *SEVERITY* > > 0 > > > > No Breathlessness* At All > > 0.5 > > > > Very Very Slight (Just Noticeable) > > 1 > > > > Very Slight > > 2 > > > > Slight Breathlessness > > 3 > > > > Moderate > > 4 > > > > Some What Severe > > 5 > > > > Severe Breathlessness > > 6 > > > > 7 > > > > Very Severe Breathlessness > > 8 > > > > 9 > > > > Very Very Severe (Almost Maximum) > > 10 > > > > Maximum > > Ian > > * > * -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openehr.org/mailman/private/openehr-clinical_lists.openehr.org/attachments/20100420/92967a8a/attachment.html>
