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UMLS Release Info

medterm4ds local data should be built from a recorded UMLS release.

Recommended raw-data location:

data/umls/

Recommended DuckDB artifact:

data/umls_current.duckdb

Build characteristics:

  • local DuckDB database
  • approximately 7.1GB
  • compact tables: mrconso, mrrel, mrsat
  • built from UMLS Metathesaurus Full Subset release files
  • supports NDC-to-RxCUI resolution through MRSAT

The downloader defaults to releaseType=umls-metathesaurus-full-subset. Use release_version or --release-version for reproducible builds, for example 2026AA.

Some UMLS release packages are flat MR*.RRF files. Other packages may contain .nlm archives with split MR*.RRF.*.gz shards. Those shards are chunks of one logical file, so the builder decompresses and concatenates them in order before DuckDB reads the table.

Release-sensitive behavior includes:

  • source counts
  • obsolete-code relationships
  • RxNorm NDC attributes
  • same-CUI mappings
  • hierarchy relationships
  • source-specific term types

Record the UMLS release version with exported ConceptMaps, value sets, and patient-friendly datasets.