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Frequency of a tablet(drug) to be taken per day - Mapping field

Hello Everyone,

I am trying to map the raw drug data from hospital to the 'Drug_exposure" table in CDM. Can anyone let me know under which field does a value like “To be taken twice a day, To be taken 3 a day”. Please note the raw data in the above case could also be 2 (twice a day), 3(thrice a day). Should it be mapped to “Sig” column? Am I right?

Looking forward to your help



Yes, you are right. We haven’t done anything to standardize this field, yet. Will have to happen soon.

I think it will also be a great idea to have a separate field where we can calculate the days of supply value, if it does not exist in the data: days of supply=actual number of tablets patients received/Sig (to be taken n times/day). Or if Sig value does not exist in the data: Sig=actual number of tablets patients received/days of supply. What do you think?

Agreed. Want to carve out how it would work and make a proposal?

Dear all:
I was wondering, if i want to show how many times to take medicine a day in “DRUG_EXPOSURE” table, how to implement it ?
I try to understand the document (OMOP CDM v6.0), but i didn’t find good solution yet.

Do you have any updates about this question?
Or did i missing something new?

Thank you for your time.


First question as always, do you have an analytic use case for this information?
Assuming you do, you have two choices, use drug_exposure.sig, “This is the verbatim instruction for the drug as written by the provider” or add a column, local to your CDM, to hold how many times a day to take the medication. Neither of these options will be accessible to the standard OHDSI analytic tools, but will make the information available in your CDM.

Hi Don Torok(@DTorok ):
Thank you for your reply.

Frequency of taking medicine maybe is kind of reason to impact treatment process or something else (I’m not sure), that is why I want to add this field.
Maybe I will choose second one , but I’m going to discuss with my partner first.

Thanks again.