Read Codes

Read codes come in two flavours: version 2 and Clinical Trials Version 3 (CTV3).

Both can be downloaded from ​TRUD.

Clusters

Read codes can be clustered into various groups for particular diseases. The details of these clusters can be downloaded from the ​QOF Business Rules page. Note that the versions change quite regularly, so make sure you have the latest version.

Here is a ​nice explanation of how to interpret the business rules.