Data Linkage

Anonymising Your Data

Researchers are able to bring their own data into the Analysis Environment, provided it is anonymised. The NDP Dementias Hub offers a Data Linkage service which uses sophisticated, deterministic and probabilistic matching technologies to create de-identified, analysis-ready data.

Supporting files and already anonymised data can be uploaded through the Analysis Platform. If data anonymisation is required, please request it during the application process.

How are the data anonymised?

  • Datasets are split into:
    • a demographic component (comprising commonly-recognised identifiers), and
    • a clinical or event component (such as medication records and procedures).
  • The demographic component is securely transferred to the SeRP Linkage Centre, a distinct linkage service operating on separate infrastructure with dedicated personnel. The clinical component is transferred independently to the NDP Dementias Hub infrastructure via a secure, web-based file upload and transfer service, maintaining separation between identifiable linkage information and clinical research data

  • The TTP anonymise and encrypt the demographic data which is then subjected to quality assurance to ensure content anonymity. Each individual record is assigned an Anonymous Linking Field (ALF) or a Residential Anonymous Linking Field (RALF) for places of residence.

  • These anonymised demographic elements of the datasets are then sent to NDP Dementias Hub ready to be loaded. They contain only the ALF, week of birth, gender code and area of residence (Lower Super Output Area of approximately 1500 head of population). They are then recombined with the clinical/event component of the dataset making them ready for linkage to other datasets for use.