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Relationship between an "episode of care", and a visit

We are thinking about how to structure our data into the OMOP CDM, and have a question about how to group clinical events.

Lets say that a patient does the following:

  1. The patient goes to a medical facility.
    a. They see their PCP, who examines them, and takes some vitals.
    b. The PCP then collects a blood sample to be sent off for some lab work.
    (The PCP then sends the patient to their neurologist for an exam)
    c. The patient then sees their neurologist and gets the exam
    d. The patient then goes to radiology for an MRI, and is consulted by the radiologist
    e. Finally, the patient stops at the pharmacy on the way out to pick up their meds

Does this example constitute a single visit (1), or three visits (a,c,d), or five visits (a,b,c,d,e)?

if the answer is greater than one, what table in the CDM can I use to group these events into a single “episode of care”?

A single visit. The various events will have different provider ids, PCP, neurologist, radiologist and pharmacists.

Thanks @DTorok, where would I store the various events then? specifically, what table would hold the records for (a,b,c,d,e)? I dont see an events table anywhere.

PCP, who examines them, and takes some vitals. – Assume maybe a diagnosis in Condition Occurrence and the results of vitals in Measurement or Observation. Blood sample set off to lab. May be recorded as a Procedure Occurrence with a CPT code. … when I said events I was referring to Condition Occurrence, Procedure, Drug Exposure, Measurement and Observation

Ah! ok thanks. I see how we could link those different types of events back to the visit thank you so much.

@kmace

You may also want to explore Episode and Episode_Event tables especially when these events (a, b, c, d, and e) can not be tied together using the same visit_occurrence_id but you still want group them into a single "episode of care’ with certain algorithm.

Please note these two tables have not been officially published yet but will be added to OMOP data model version 6.1. But the DDL and and documentation are officially released. So feel free to use them and provide us feedback.

Hi @kmace ,

Have you checked the visit_detail table? It may be exactly what you need.

I agree with @jposada

#1 would be a Visit Occurrence record with visit_concept_id = 9202

a,c,d,e are all records in the Visit_Detail table. a and b are one Visit_detail record because the blood sample is taken during the visit with the PCP.

OR if you view a,c,d,e as separate outpatient visits, you can also create separate records in the Visit Occurrence table. But it sounds like the first option meets your use case

t