CommonDataModel
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OHDSI
Revisit the *_ERA queries
Right now the ERA queries use all data to create eras, even data outside of observation periods. We should make a decision on how the eras should be built and revise the queries accordingly.
Yikes. Let's bring it on. Obviously, the closed system with the two axioms (everything that happened has a record, if there is no record it didn't happen) is only defined to be true within the observation period.
@cgreich I am going to add it to our list of conventions to discuss in the coming year.
Is the "DOSE_ERA" SQL available on the CDM website? I don't see it here https://ohdsi.github.io/CommonDataModel/sqlScripts.html.
the two axioms (everything that happened has a record, if there is no record it didn't happen)
I think the second axiom is equivalent to the first. In logic (A implies B) is equivalent to (not B implies not A) where the latter is called the contrapositive of the former.
So let A = "it happened" B = "there is a record"
(If it happened then there is a record) is logically equivalent to (if there is no record then it did not happen)
I don't mean to be pedantic. Just pointing out we only need one axiom and get the second statement for free as an implication. This is the first time I've heard these axioms.
What about this for axiom 2? "If there it didn't happen there is no record" Then observation periods give us: "There a record if and only if it happened."
Linking related issue to add era scripts to the DDL https://github.com/OHDSI/CommonDataModel/issues/551