How to handle multiple types of observation_period (i.e. medical eligibility and pharmacy eligibility) in ETL

[Adam_Black]

Suppose I have both medical claims, medical eligibility records, pharmacy claims, and pharmacy eligibility records populating an OMOP CDM. Is there a convention for how to include both medical and pharmacy eligibility information in the observation_period table?

Some options are:

1. Use only medical eligibility to derive observation_period. Only include pharmacy claims that occur during a period of medical eligibility.
2. Use the intersection of medical and pharmacy eligibility to derive observation_period.
3. Use the union of medical and pharmacy eligibility to derive observation period.
4. Use both medical and pharmacy eligibility but split up observation periods into three types of observation: Medical only, pharmacy only, both medical and pharmacy. Possibly use the period_type_concept_id to store the type of observation period.
5. Create two separate observation_period tables, one from medical eligibility and one from pharmacy eligibility
6. Create two separate CDMs one for medical claims/eligibility and one for pharmacy claims/eligibility

Has anyone else tackled this issue?

[Christian_Reich]

@Adam_Black:

This has been discussed heavily before. The conclusion is: 2. Intersection. If you have medical and drug eligibility you need to do the intersection. If you don’t have one of them at all obviously you can only pick the one you have. But a database only with drugs is not that useful for most of the OHDSI use cases.

However, still write all the records you have, even if they fall outside the Observation Period.

[Adam_Black]

However, still write all the records you have, even if they fall outside the Observation Period.

Thanks! I did not realize this!