sct proximal-primitives
Compute a concept's proximal primitive supertypes: the most specific primitive concepts that subsume it (or the concept itself, if it is primitive).
When to use: classification and post-coordination QA, where a concept's necessary normal form is expressed in terms of its proximal primitive supertypes plus refinements. Every concept has at least one, since the root concept (138875005) is primitive and subsumes everything. For the full ancestor chain instead, use sct diagram --view ancestors; for a raw subsumption test between two concepts, use the SDK's Snomed::subsumes.
Usage
sct proximal-primitives <CONCEPT> [--db <FILE>] [-f text|json|yaml]
Options
| Argument / Flag | Default | Description |
|---|---|---|
<CONCEPT> |
(required) | Focus concept SCTID. |
--db <FILE> |
discovered (see Path resolution) | SQLite database produced by sct sqlite. |
-f, --format <FMT> |
text |
Output format: text (human), json, or yaml. |
Requires schema v6 or later (the definition_status column, added alongside RF2 definitionStatusId). Rebuild an older database with sct ndjson then sct sqlite to add it.
Examples
# Most specific primitive ancestors of a fully-defined concept
sct proximal-primitives 22298006
# Raw JSON for scripting
sct proximal-primitives 22298006 --format json
# Explicit database
sct proximal-primitives 73211009 --db /data/snomed.db
Text output writes one id<TAB>preferred_term line per result, followed by a stderr summary line. A concept that is itself primitive returns only itself, since nothing in its ancestor set is more specific. A concept with multiple incomparable primitive ancestors (multiple inheritance from unrelated primitive branches) returns all of them.
Algorithm
- Collect the concept itself plus all of its transitive ancestors (using the transitive-closure table when present, otherwise a recursive CTE - see
sct tct). - Filter to those with
definition_status = 900000000000074008(primitive). - Drop any primitive that is itself a proper ancestor of another primitive still in the set, leaving only the most specific ones.
An error means either the database predates the definition_status column, or (for a database with the column but incomplete data - e.g. records carried over from schema v5) no primitive ancestor could be found for the concept.