The DSRU’s epidemiologists conduct studies using CPRD, the UK’s database of NHS primary healthcare records

The DSRU’s epidemiologists are experienced in conducting studies using real-world data (RWD) from the Clinical Practice Research Datalink (CPRD), the NHS observational data service, based in the UK.

Regulators are increasingly recognising the importance of RWD during the pre- and post-marketing phases. The UK healthcare system is well-suited to the RWD approach, and the CPRD research service provides unique opportunities for researchers to utilise the power of a longitudinal health dataset to answer a range of research questions.


The DSRU team uses CPRD data in a variety of study designs.

DSRU uses CPRD data to investigate various research questions in pharmacovigilance and pharmacoepidemiology, including:

  • Studies to fulfil post-authorisation regulatory requirements (PASS), including those which form part of the product’s risk management plan
  • Studies to support drug development, marketing authorisation application and extension of license
  • Drug utilisation studies
  • Safety studies investigating exposures and outcomes of interest over time

The CPRD dataset contains electronic primary healthcare records of 16 million active patients and is representative of the wider UK population. For further information about CPRD, click here.

Case Study 1

Extension of product licence

  • We were approached by a company which requested a CPRD study to support extension of a product licence to a new age group of patients.
  • CPRD was chosen because it reflects real-world use from electronic medical records and can provide information on use in groups which are not covered by the current licence.
  • Real-world data is becoming used more frequently to support licence extension applications and has several advantages over clinical trials, including lower costs.
  • The DSRU was able to advise that regulators frequently accept this type of study to support license extension applications.
  • A CPRD study was proposed to provide data on safety and utilisation of the medicinal product in an age group not covered by the current licence.
  • The study population comprised patients who received the product in the primary care setting in the UK within the new age group of interest.
  • Variables collected included age, sex, daily dose, duration of treatment, concomitant medications, prior medications, medical history, safety events, weight at baseline, test results at baseline and 3 months after starting treatment.
  • The DSRU team conducted the study on the CPRD GP Online Data (GOLD) database in the UK.
  • The study was completed within 8 weeks, including data extraction, preparation, analysis and production of final report.

Case Study 2

Use of CPRD data to monitor the safety of COVID-19 vaccines

  • The DSRU is collaborating with several other research institutions throughout Europe, under the VAccine monitoring Collaboration for Europe (VAC4EU) study network.
  • This independent network is conducting post-authorisation safety studies (PASS) for each of the COVID-19 vaccines marketed throughout Europe, to fulfil regulatory requirements set out by the European Medicines Agency (EMA).
  • The DSRU forms the UK arm of this international group.
  • We are using electronic primary healthcare record data from CPRD Aurum to monitor the safety of COVID-19 vaccines, contributing to studies on COVID-19 vaccines manufactured by Pfizer/BioNTech, AstraZeneca, and Moderna.
  • Each of these studies is monitoring the frequency of adverse events of special interest (AESI).
  • We use de-identified CPRD data to form cohorts of patients who have and have not received the COVID-19 vaccine of interest. We then use the medical records to search for those who have developed an AESI in each group. We compare the frequency of AESI within vaccinated individuals with the frequency of these events in unvaccinated patients.
  • In the Moderna vaccine study, there is also a signal detection step. Incidence rates of AESI are compared with pre-pandemic background event rates. This highlights any adverse events occurring within vaccinated individuals which are yet to be characterised.
  • Aggregate results from the UK arm are combined with aggregate results from the other research partners. The use of CPRD data in this way contributes to an overall picture of vaccine safety within Europe.
  • Regular interim reports are provided to the EMA, enabling the regulators to monitor the safety of these vaccines on an ongoing basis.
  • The final reports for each of the studies are expected in 2024.