There is no good way to track temporal code changes in OMOP. We generally assume that various descriptions provided by ICDO are synonymous names of the same morphology. So no matter when does the diagnosis occurs, semantical meaning should not change. To be fair, there are vocabularies, like NDC, where this is not always the case. However, ICDO3 does not really seem to have this problem. In case of Sinonasal papilloma, exophytic, it still keeps alternative description of “Urothelial papilloma, inverted” with Related status in 3.2:
ICDO3.2 |
Level |
Term |
8121/0 |
Preferred |
Sinonasal papilloma, exophytic |
8121/0 |
Synonym |
Schneiderian papilloma, NOS |
8121/0 |
Synonym |
Sinonasal papilloma, NOS |
8121/0 |
Synonym |
Sinonasal papilloma, fungiform |
8121/0 |
Related |
Urothelial papilloma, inverted |
8121/0 |
Related |
Transitional papilloma, inverted, NOS |
8121/0 |
Synonym |
Transitional cell papilloma, inverted, NOS |
(taken from here)
We do not preserve “Related” concepts as synonyms in OMOP, because they are likely subcategories of their “Preferred” terms, and it may be incorrect to fully equate them.
For Condition domain, we try to align everything to SNOMED. The main reason for this decision is SNOMED’s multi-axial hierarchy. For example, SNOMED allows user to create concept sets for all malignant neoplasms, tumors of skin regardless of malignancy or lymphoproliferative disorders with one button. ICDO does not have that.
ICDO concepts are made non-standard only in cases where their meaning fully aligns to existing SNOMED concepts with defined attribute set, and are mapped to the latter. Standard ICDO concepts don’t have exact equivalent in SNOMED and are instead assigned ancestors among SNOMED concepts, as close as possible (example, see ‘Is a’ relationships). In both cases, concept sets created from SNOMED concepts will have all intended ICDO concepts included.
There is a consideration for OMOP to have own extension of SNOMED, so that necessary concepts could be created to support mappings from currently standard ICDO concept, but there is no ETA for this yet.