Definition

The Coding_ClinicalCode extract is the central reference table for all coded clinical terminology used across the IM1 extract. It maps EMIS internal code identifiers to their corresponding Read v2 terms, SNOMED CT concepts and descriptions, national codes, and EMIS-specific category descriptions — providing the lookup layer needed to interpret coded entries in clinical tables.

Information

The Coding_ClinicalCode extract is a reference table scoped per agreement. Each record includes an agreementid, generated by a cross join with the active feed schedule — meaning the same clinical code data is replicated for every active agreement in the extract run. It serves as the terminology reference for all coded clinical records in the feed, including observations, diary entries, consultations, appointments, and referrals.

Each code record is uniquely identified by codeid, with parentcodeid supporting hierarchical code relationships.

Key Identifiers

• codeid: The unique EMIS internal identifier for this clinical code. This is the join key used in all clinical tables.
• parentcodeid: References the parent code in the EMIS code hierarchy, enabling navigation of code family trees.
• readtermid: The Read v2 term identifier (5-byte code).
• snomedctconceptid: The SNOMED CT concept identifier for international interoperability.
• snomedctdescriptionid: The SNOMED CT description identifier, providing the specific preferred or synonym term.

Descriptive Fields

• term: The display term for the code as shown in EMIS Web.
• nationalcode: The national code value, if assigned.
• nationalcodecategory: The category of the national code.
• nationaldescription: The description associated with the national code.
• emiscodecategorydescription: The EMIS-specific category classification for the code (e.g., Allergy, Immunisation, Referral) — used to distinguish observation subtypes.

Practical Use

flowchart TB
  subgraph container["Data Collection"]
    n1["Clinical Code"]
    n2["Read Code & SNOMED ID"]
    n3["Code Description"]
  end

  n17["EMIS Clinical Code System"] --> container
  n18["SNOMED CT Reference"] --> container

  container --> n16["Gather clinical codes"]
  n16 --> n14["ETL"]
  n14 --> n15["Coding_ClinicalCode Model"]