SNOMED CT and ICD: two jobs

Both describe diagnoses. So why both?

Two code systems, and health systems use both.

One represents, one classifies

• SNOMED CT: A clinical terminology: it represents, in detail, what clinicians record.
• ICD: A statistical classification: mortality statistics, clinical documentation, resource allocation, case mix, patient safety and quality of care.

Neither is wrong

• A terminology: Can hold fine clinical detail, and many ways of saying it.
• A classification: Groups cases into categories that don't overlap, so they can be counted.

A map links the two

• A map: Directed relationships from a SNOMED CT concept to one or more ICD-10 codes.
• Where it sits: In the same release package as the International Edition, but a supplement to it, not part of it.
• Scope: Only active, precoordinated concepts in the hierarchies that overlap with ICD-10.

Keep these in mind

• A terminology represents
• A classification counts
• A map connects them, and doesn't replace judgement