What FHIR resource is needed to identify a De NOVO patient

We have a requirement to send in information whether the patient is De NOVO patient or not? De NOVO patient do not go through the early breast cancer and they are diagnosed with metastatic breast cancer directly. Is there any FHIR resource that I can use to transmit to the server that the patient is De NOVO?

Any help in this matter is appreciated.

It sounds like a condition, but how do you use this data?

We are using this information to distinguish patients who have no medication information vs patients who have medication information but did not enter any information. I do not know if there is a better way to identify.

Can you just search to see if they have medication records?

On the patient information capture form, we are asking whether the patient had any medications before. If the patient answers no then we treat them as DeNOVO and if the patient chooses yes and did not enter any medication information, they are not DeNovo patients. In both cases the medication history will be empty.

What information capture form? Is that a questionnaire?

If you’re wanting to use it as a filter, I’d probably capture the question and answer as an Observation. You could then retrieve your list of patients by searching for that specific Observation where the value was ‘no’ and do an _include on Patient. (You could also capture the question and answer using Questionnaire, but you couldn’t use that for a search.)