Read to Snomed CT map explorer

Map details
The results box

Most of primary care in the UK will be moving from Read codes to Snomed CT in April 2018. There is a huge amount of data already held on practice computer systems and this will be moved to Snomed CT using a map.

I am quite interested in this map, both from a curiosity about how these things work and also a need to understand how the data about my patient will appear after the change.

Currently the computer systems are using Snomed to a degree. Snomed CT was partly created out of Read codes so there is a pretty good mapping of concepts. Computer systems are currently using these concepts but with the Read code heirarchy used in place of the Snomed one.

My approach to this site is to explore the map. None of this is a prediction but is a way of applying the Snomed heirarchy to the current Read codes. My practice uses EMIS and they plan to leave current searches as they are. That will mean that they don't change on day one but will become increasingly unpredictable as more concepts without a Read code equivalent are used in records.

Similarly a list of patients with diabetes will look different depending in which heirarchy the searches are done. I am interested in which concepts appear as children but were not before and which no longer apply.

Snomed CT is, in almost all cases, more accurate than the Read code system. However it is different, and this is my way of exploring the differences.

Gavin Jamie September 2017

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