Code lists

In primary care in the UK, a patient’s health-related information is electronically recorded and coded. Common methods of coded data entry are the Read code and SNOMED classifications. In our research, we have used rigorous consensus approaches to deriving definitions and code lists for morbidities. These are adapted depending on requirements of individual studies. Our code lists and definitions given below are free for others to use but we ask that you acknowledge us appropriately, preferably through reference to the relevant publication(s). If there is no related publication, then please reference

We strongly advise that these code lists are checked carefully before use as they are likely to require adaptation and/or updating for individual studies. The linked publication for each code list is detailed where applicable.

If you have any queries about our code lists, you are looking for a code list not listed here, or would like to ask advice, please email James Bailey (

Click the links below to access the related code lists: