UCUM units?

[Mauvila]

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Description

Will there be UCUM units in MIMIC IV?
I realize that you try to reach a balance between presenting the raw (ie original) data vs presenting corrected (and thus more useful) data, and I assume the raw data doesn't contain UCUM units. I think a supplementary table could allow you to both present the raw data and present more useful corrected data at the same time.

For example, a table called something like 'supp_units' could have columns:
-item ID (including both d_items and d_labitems item IDs)
-raw unit (the original 'valueuom')
-UCUM unit

The composite of the item ID and raw unit columns would be unique. I'm not even sure the 'raw unit' column would be needed, but if present, you could easily add a fourth column called 'LOINC code'. As item ID:LOINC code relationship might be "one to many" (or "many to many"), the inclusion of the raw unit value would help distinguish which LOINC code to use.
And by adding a LOINC column to an auxiliary (ie non-original [raw] data) table, you can leave the raw data LOINC code in place in the d_labitems (etc) table while presenting the better LOINC code in a different table without worrying about affecting those who desire just the raw data (ie those who want to clean the data themselves).

J Allen

[alistairewj]

It's unclear how much standardization will be done in MIMIC-IV but this is a good issue to keep open so we can discuss it when the time is right.