The following standard linked datasets are now available:
- Hospital Episodes Statistics (HES) Admitted Patient Care (APC), with coverage to end March 2023
- HES Outpatient data, with coverage to end March 2023
- ONS deaths data, with coverage to beginning April 2024
- Small area deprivation data (Index of Multiple Deprivation, Townsend and Carstairs index) and Rural-Urban Classification, at the patient level
This refresh of the linked data is based on EMIS and Vision cohorts from 2022, so will not include linked data for patients who have more recently registered at existing practices or for patients at practices newly contributing data to CPRD since that time.
These data have been linked using a different linkage method to previous releases, with linkage via the NHS England Data Processing Service Personal Demographics Service (PDS) and Master Person Service (MPS). Linkage is via PDS where a match on NHS number and date of birth can be made; if not matched via PDS, then the MPS process attempts to ascertain a match based on gender, date of birth and either a local patient identifier or postcode.
The criteria for linkage eligibility are also slightly different (patients must have a valid NHS number and date of birth before linkage is attempted). Given these differences, we advise users to familiarise themselves with the user guidance, available on the NHS England website: https://digital.nhs.uk/services/personal-demographics-service/master-person-service. We have included a summary of the impact of this change on the linked CPRD cohort in the Source file documentation.
Requests for linked data are made via the CPRD electronic applications portal, eRAP, and guidance is available on our Requesting linked data from CPRD web page.
Please note the information on our Pricing web page regarding data redelivery fees, which are applied per delivery event not per dataset delivered (Type 1 and Type 2 linkage requests are two separate delivery events). Redelivery requests must be formally initiated by submitting a Data Update Request here: Data Update Request. A data destruction certificate for the data previously delivered must be submitted before the new linkage request can be processed.