We are currently using the Archetype Designer to create a template for recording historical medications.
One of the issues we’ve come up against is adding custom units to the list available in the “Dose” node (Quantity type).
Specifically, we want to be able to add things like “Tablets”, “Puffs”, “Drops”, etc to the list. So when a medication with a specific dose is selected, the clinician can use one of these units to accurately record the dose.
e.g. Medication = Paracetamol 500mg, Dose = 2 tablets, Timing frequency = 4/day
The Archetype Designer only seems to allow us to select units that are in the UCUM or openEHR set. And doesn’t allow us to add any custom units.
I’m not aware of the details. @siljelb would best answer this question, but she may be unavailable for some time. So let me know if you want me to try and dive in to help.
The openEHR Reference model was updated recently to allow the use of such custom units but I am not clear if it is supported yet in Archetype Designer or in the various CDRs.
The work around in the Medication archetypes was to hold the amount as a ‘qualified real’ (UCUM unit ‘1’) with a separate element to hold the custom unit…
We can try to find out from tech colleagues where we are in terms of wide support for the new arrangement.
Ian’s response pretty much sums up the current situation. I’d only like to add that if you need to do this in the short term and there isn’t tooling support, I’d use the previous published versions of the relevant archetypes. They’ve been set as deprecated, so you’ll need to search specifically for them, see below:
