Approach on recording medication orders that are cancelled due to CDS alerts

Implementers
1

Hello,

I have a use case whereby we need to be able to record instances of when a medication was prescribed and the order was cancelled due to an alert generated by the decision support system.

I was thinking of using the drug_exposure table to capture the prescription record and record the stop_reason being “Cancelled due to CDS alert”. Is this approach valid?

Regards,
Vimala

2

I don’t think so. Exposures should be drugs that you think actually happened. If you know the exposure started, but then canceled shortly after, set the drug exposure end date to when it was canceled. If it is a prescription but was canceled before it began, don’t put anything in the drug exposure table (since you know the patient wasn’t actually exposed). If you want to record the cancellation event, the OBSERVATION table would be the place to store observed events such as ‘medication canceled’ (full disclosure, not sure if this concept actually exists), but if it does, you can use the concept ID for drug cancelation and the ‘value_as_concept’ can be the drug concept that was being canceled.

-Chris

3

@Vimala_Jacob, I did a search on ATLAS for ‘cancel’ :
http://www.ohdsi.org/web/atlas/#/search/cancel

Found this one: “Batch Perscription cancelled”:
http://www.ohdsi.org/web/atlas/#/concept/44804722

Or this one: “Perscription Cancelled”
http://www.ohdsi.org/web/atlas/#/concept/44805039

This is a standard concept, from the SNOMED vocabulary, that maps to the Observation domain. Sounds like it would fit your purposes.

-Chris

4

Hello Chris,

Thanks for your advice and for putting me on the right path! I have never used ATLAS before. Is that a vocabulary browser?

Also I had a secondary question around the approach you suggested regarding cancelled prescriptions. If say a prescription was ordered and administered, would the medication order be recorded in the OBSERVATION table and the drug administration in the DRUG_EXPOSURE table?

Regards,
Vimala

5

How would we store the reason for the prescription being cancelled?

6

Atlas is a multi-function tool. One use case is vocabulary exploration. Another is cohort definition.

Re: your second question: if you wanted to record a “prescription order event” then I’d say sure, create an observation record for the order, store it in Observation, and if you have a study where you want to find an order that was made in proximity to a drug exposure, you’d write your query to do that. Alternatively, I belive there’s a Drug_Type_Concept_id column in drug exposure that can describe where the record came from. For example:
Prescription dispensed in pharmacy: http://www.ohdsi.org/web/atlas/#/concept/38000175
Prescription dispensed through mail order: http://www.ohdsi.org/web/atlas/#/concept/38000176

So you can look for drug expsorues based on how they were ordered in this way. May be limited tho, based on the granularity of the concept types.

7

I’m not exactly sure on this one. If there was an observation concept for reason for cancellation there you coudl store it in the observation table. If you wan to link a record from the drug_exposure table to the observation_table (such as the drug exposure was canceled due to the reason in the observation table) then you can use this feature called ‘fact_relationships’ but I can’t help you much there, but @Christian_Reich may have some suggestions there.

-Chris