And a couple of other potential use cases:
https://athena.ohdsi.org/search-terms/terms/725460
Measurement of Transaminases is mapped to Measurement of liver enzymes in general (it doesn’t make a practical problem, as it’s the only source code that’s mapped to ‘Measurement of liver enzymes’)
all these codes are mapped to the one code: 372629 Nonexudative age-related macular degeneration, while on a practice we need to distinguish between these codes (for example, we are interested in Geographic atrophy
which is an advanced stage coded as H35.31_(3|4) , not all these codes
