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What to do with lab tests without values?

CDM Builders
#1

Hi all. This has probably been discussed at length, but I can’t find it (I read this and this related discussion, and looked at the documentation of the procedure_occurrence and measurement tables). So apologies in advance for asking what I probably should know:

I have a (Japanese) claims database that contains many claims for lab tests. Example descriptions are:

  • “alanine aminotransferase (ALT)”
  • “aspartate aminotransferase (AST)”
  • “total bilirubins (TBIL)”
  • “alkaline phosphatase (ALP)”
  • “uric acid (UA)”
  • “low density lipoprotein (LDL) cholesterol”
  • “free triiodothyronine (FT3)”

I only see the claims for the test procedures, I don’t have the lab values.

I don’t see corresponding Standard concepts in the procedure domain, so I cannot record these in the procedure_occurrence table. Should I record them in the measurement table instead, without values? Or just discard them altogether?

(@Azza_Shoaibi)

#2

The convention in the CDM is that a MEASUREMENT record is the occurrence that a measurement took place, regardless of whether the value associated with the measurement is recorded. So, all of these lab tests should be mapped to standard concepts, most will be in LOINC, but some may be in SNOMED or CPT4, these concepts will be in the ‘measurement’ domain, and accordingly we generate records in the MEASUREMENT table, with the VALUE_AS_NUMBER and VALUE_AS_CONCEPT_ID being NULL.

#3

Patrick’s answer is what we do. I might just add that any additional information can also be stored in the measurement.value_source_value along with measurement.measurement_source_value such as comments/indicators that might be useful to have down the road about why this measurement did not have a value.

#4

Thanks!

t