sct read2

Import the final NHS Data Migration Read v2 maps from TRUD item 9 into an existing sct SQLite database.

Most users should prefer the one-command workspace build:

sct trud download --multi-terminology

That downloads the UK Monolith, builds SQLite with inactive concepts and all RF2 maps/history, downloads TRUD item 9, and imports Read v2 into the same database.

Use sct read2 import when you already have both files locally.

Usage

sct read2 import --archive nhs_datamigration_29.0.0_20200401000001.zip --db snomed.db

What It Imports

The importer reads the primary clinically assured Read v2 map:

Mapping Tables/Updated/Clinically Assured/rcsctmap2_uk_20200401000001.txt

It applies the active-map rule from the NHS Data Migration documentation:

1. Group rows by MapId.
2. Keep the latest EffectiveDate row for each MapId.
3. Store it with active = MapStatus > 0.
4. Query commands use active rows by default.

Rows are stored in crossmaps as read2 -> snomed mappings. The importer preserves:

• ReadCode + TermCode source key, e.g. 0111.00
• target SNOMED concept
• target DescriptionId
• IS_ASSURED
• MapId
• EffectiveDate
• MapStatus
• item 9 source provenance

For compatibility with older code paths, active Read v2 rows are also written to the legacy concept_maps reverse-lookup table.

Examples

# Download item 9 only
sct trud download --edition nhs_data_migration

# Import it into an existing SNOMED database
sct read2 import \
  --archive ~/.local/share/sct/releases/nhs_datamigration_29.0.0_20200401000001.zip \
  --db snomed.db

# Use the imported maps
echo '0111.00' | sct map --from read2 --to snomed --db snomed.db
sct map 0111.00 --from read2 --db snomed.db

Notes

The Read v2 source key is the five-character ReadCode plus the two-character TermCode, with no separator:

<ReadCode><TermCode>

For example, 0111. + 00 becomes 0111.00.