Real World Evidence in Primary Care

Why GP data is the richest source of real-world evidence in the NHS — and how it's transforming drug development and market access.

What Is Real World Evidence?

Real world evidence (RWE) is clinical evidence derived from data collected outside of traditional randomised controlled trials — from routine clinical practice, electronic health records, patient registries, and observational studies. Unlike RCTs, RWE reflects how treatments perform in everyday clinical settings, in the full diversity of patients who will actually use them.

RWE is increasingly valued by regulators, payers and health technology assessment bodies including NICE, as it addresses questions that RCTs cannot: long-term safety, real-world effectiveness, adherence, and outcomes in patient subgroups typically excluded from trials.

Why Primary Care Is the Richest Source of RWE in the UK

UK general practice holds longitudinal health records for virtually the entire population. EMIS Web and SystmOne — the two dominant GP clinical systems — together cover over 95% of GP practices in England and hold decades of coded clinical data including diagnoses, prescriptions, investigations, referrals, and outcomes.

This makes primary care EHR data uniquely powerful for RWE. Hospital data captures acute episodes; primary care data captures the full disease journey — from first symptom to diagnosis, treatment, long-term management, comorbidity, and death.

Types of RWE Studies in GP Settings

Retrospective Cohort Studies

Using historical EHR data to compare outcomes between patient groups. Rapid, low-cost, and increasingly accepted by regulators for post-authorisation safety and effectiveness studies.

Prospective Observational Studies

Following patients forward in time within their normal care pathway, collecting additional data points not routinely recorded. Can be linked with patient-reported outcomes and biosamples.

Hybrid RCT/RWE Designs

Randomised at the practice level (cluster RCTs) or using pragmatic trial designs within real clinical workflows. Increasingly favoured for effectiveness research where blinding is impractical.

RWE for Market Access and NICE Submissions

NICE increasingly requests RWE to support technology appraisals, particularly for managed access agreements and post-launch evidence generation. Primary care data is particularly valuable for NICE submissions because it reflects the population in which the treatment will be used — not the selected population of a regulatory trial.

Ethical Considerations and Data Governance

All use of patient data for research requires appropriate governance. This includes Caldicott Guardian approval for each practice, Data Protection Impact Assessment (DPIA) where patient-level data is used, and either patient consent or an appropriate legal basis under UK GDPR. PCRA has established data sharing agreements across its network of practices to facilitate efficient, compliant RWE data access for sponsors.

Planning an RWE study in primary care?

PCRA has established data sharing agreements and experienced research leads across 30+ practices. Talk to us about your study design.

Contact PCRA →

Planning a real world evidence study?

PCRA provides access to consented GP practice populations and experienced research teams across the network.

Talk to PCRA →