1
Primary use and cross-border care
EHDS expects access to, and transmission of, priority clinical information using a common European exchange format, with cross-border exchange through MyHealth@EU and national contact points.
1. Executive judgement
Purpose
This is a generic comparative reference. It describes how secondary-care integration is organised across the four UK nations and how those architectures relate to emerging EHDS concepts. It does not assume a single UK-wide system, recommend a particular product architecture or assess any specific implementation.
Analysis
There is no single UK secondary-care integration architecture. The four nations share standards and many clinical concepts, but expose materially different integration surfaces. England is predominantly a set of explicit national APIs and services; Wales is closer to a nationally integrated platform and shared-repository model; Scotland combines established national and Board services with a transition towards the National Digital Platform; Northern Ireland has consolidated secondary and community care around encompass/Epic, with primary care remaining outside that boundary.
This means meaningful comparison should be made capability by capability, asking where information originates, which national or regional service mediates it, whether the flow is read, write or bidirectional, and whether the route is a public API, national message service, shared repository, portal or local integration.
Assurance
The comparison is sufficiently evidenced to support architecture discovery and informed comparison. It is not a substitute for nation-specific onboarding, contractual confirmation or local integration discovery.
Particular caution is required for Northern Ireland external APIs and for Scottish services still moving towards target-state NDP patterns.2. The four national integration patterns
European comparison
Alignment with the emerging European Health Data Space architecture
EHDS provides a useful external reference architecture even though the four UK health services are not EU Member State implementations. This comparison assesses structural and technical alignment, not legal compliance or certification.
Legal and architectural context
Fact: Regulation (EU) 2025/327 creates a common architecture for primary use, secondary use and EHR-system interoperability. The first primary-use priority group is Patient Summary plus ePrescription/eDispensation from March 2029; imaging, medical test results and discharge reports follow from March 2031. The detailed European electronic health record exchange format (EEHRxF) and several other implementing specifications are due by 26 March 2027. WEB-19 · WEB-20
Analysis: Because those detailed implementing specifications are still emerging, a UK system cannot meaningfully claim full EHDS conformance in September 2026. The useful question is whether national architecture would make future mapping to EHDS comparatively straightforward.
Scope caution
Fact: MyHealth@EU connects EU national infrastructures through National Contact Points for eHealth, while HealthData@EU provides the federated secondary-use model. None of the four UK nations currently operates as an EU Member State node in those infrastructures. WEB-21 · WEB-23
Legal/professional inference: Northern Ireland's Windsor Framework position should not be treated as making EHDS automatically applicable. New EU acts require the specific Windsor Framework process before they apply in Northern Ireland. WEB-28
2
Interoperable EHR systems
EHR systems are expected to provide harmonised interoperability and logging components, support import and export of priority data in EEHRxF, and pass defined digital testing and conformity processes.
3
Secondary use
EHDS introduces health data access bodies, dataset discovery, data permits, secure processing environments and the federated HealthData@EU infrastructure for research, innovation, policy and regulatory uses.
Overall architectural alignment
England
Strong national APIs, FHIR-based services, patient identity, e-referral, prescribing, patient access and a growing SDE model align well with EHDS principles. The principal gap is that imaging, laboratory and discharge exchange remain less uniformly national than EHDS's eventual priority-category model, and there is no MyHealth@EU gateway.
Wales
Wales is structurally the closest of the four: national MPI, shared repositories, medicines, diagnostics, patient access, FHIR R4/UK Core direction, terminology services, a National Data Resource, data catalogue and Secure Data Environment create a coherent national architecture. Formal EEHRxF compatibility and an EU gateway are not established.
Scotland
The National Digital Platform, CHI, FHIR-based Care Summary direction, national PACS work, MyCare.scot and a mature Safe Haven network are compatible with EHDS thinking. Alignment is constrained by the coexistence of Board-level and legacy services while the national architecture is still being consolidated.
Northern Ireland
encompass provides unusual regional EPR consolidation, supported by NIDIS, My Care and established secure research access. That gives strong internal data availability, but public evidence is weaker on open public interoperability, portable exchange profiles and machine-to-machine access across the GP boundary.
Dimension-by-dimension comparison
| EHDS dimension | England | Wales | Scotland | Northern Ireland |
|---|---|---|---|---|
| National exchange and gateway architecture | Explicit national service fabric PDS, e-RS, GP Connect, SCR/NRL, MESH and NEMS provide a rich national integration surface, but not one EHDS-style national contact-point gateway. |
Coherent national platform MPI, CDR, WCRS, WCP and national APIs make Wales structurally close to the idea of a national exchange gateway. |
National platform emerging NDP is moving Scotland towards a common gateway model, while Board and legacy services remain operationally important. |
Regional consolidation encompass greatly simplifies internal secondary-care exchange, but external machine-to-machine gateway arrangements are less transparent. |
| EHDS priority clinical categories | Good coverage, uneven nationalisation Patient summary and medicines are strong nationally. Imaging, laboratory results and discharge data are supported, but often through provider or regional routes rather than one national exchange layer. |
Broad national coverage Shared medicines, diagnostics, imaging/report access, discharge documents and shared-record services cover most EHDS priority domains nationally. |
Coverage exists but is mixed ECS/KIS, Care Summary and national imaging direction align, but tests and discharge remain more heterogeneous. |
Strong inside encompass Priority categories are largely available inside the regional EPR, but cross-boundary exchange with GP and external systems is less standards-transparent. |
| Open exchange format, portability and EHR interoperability component | Strong FHIR direction National APIs and UK Core-related patterns are favourable, but mandatory EEHRxF import/export and EU harmonised-component conformity are not part of the UK regime. |
Open architecture is explicit DHCW's FHIR R4, UK Core, terminology and open-platform direction give Wales a strong mapping position when EEHRxF is finalised. |
FHIR target-state, mixed estate NDP services are increasingly standards-based, but portability is affected by coexistence with older Board infrastructure. |
Portability evidence is limited Regional consolidation is operationally strong, but public evidence does not establish an open, profile-governed export/import contract equivalent to the emerging EHDS interoperability component. |
| Patient access, control and access logging | NHS App and national identity Strong patient-facing infrastructure and national authentication exist, although EHDS-specific data rights and harmonised logging formats are distinct requirements. |
NHS Wales App plus national audit services Patient access is expanding and the national platform exposes audit capability. EHDS rights and logging specifications would still need explicit mapping. |
MyCare.scot is emerging The national digital front door is directionally aligned but not yet equivalent to the mature rights and logging architecture envisaged by EHDS. |
My Care and single-record auditability Regional EPR consolidation supports access visibility, but public evidence does not demonstrate alignment to the EHDS logging component specification. |
| Secondary use: catalogue, access process and secure environment | SDE direction is strong NHS England is moving research and planning access into SDEs, closely matching EHDS secure-processing principles. The HDAB and HealthData@EU governance model is different. |
Closest structural match NDR combines national data infrastructure, a data request service, catalogue capability and SDE. This resembles several core HDAB functions even though it is not an EHDS body. |
Mature federated Safe Haven model Scotland's national and regional Safe Havens provide controlled secure processing with strong governance and are structurally close to the EHDS secure-processing model. |
Established regional SDE The Honest Broker Service and emerging NITRE provide a strong regional secure-research architecture, although not the EHDS data-permit and cross-border governance model. |
| Readiness to connect to MyHealth@EU / HealthData@EU | No current EU gateway Technically adaptable, but no Member State National Contact Point or EHDS connection exists. |
Architecture could support a gateway National platform coherence is favourable, but no current MyHealth@EU or HealthData@EU connection exists. |
NDP gives a plausible future attachment point No current EU gateway exists and the domestic architecture is still converging. |
No automatic Windsor route Technical proximity to Ireland may make interoperability strategically valuable, but EHDS does not automatically apply through the Windsor Framework. |
Architecture and interoperability implications
Implications for architecture and interoperability practice
- Keep the six EHDS priority categories explicit in the information architecture. Patient Summary, prescriptions/dispensations, imaging, tests/results and discharge reports should each have governed import/export contracts rather than being hidden inside generic document exchange.
- Keep national integration boundaries explicit. National APIs, repositories, gateways and messaging services should be treated as distinct architectural boundaries so that future UK-to-EU exchange can be added without distorting domestic clinical architectures.
- Preserve provenance, terminology and source identifiers. This will matter when mapping UK Core, national profiles and terminology into the final EEHRxF specifications.
- Make audit data exportable. EHDS treats logging as a harmonised EHR component, so audit should not be an opaque vendor-only subsystem.
- Treat portable structured export as an architectural requirement. Even before EEHRxF is final, systems should support loss-aware export and re-import of priority clinical information using open, documented formats.
- Keep secondary-use architecture separable from operational clinical-system storage. Data catalogue, access approval, secure processing and disclosure controls should be capable of mapping to an HDAB/HealthData@EU-style operating model if cross-border participation later becomes desirable.
Assessment basis: qualitative architectural alignment as at 13 September 2026. Green means structurally close to the emerging EHDS model; Amber means materially aligned but incomplete or transitional; Amber–Red means a significant architectural or governance gap. These are not legal compliance ratings.
3. Capability comparison matrix
The matrix deliberately compares capabilities and data flows, rather than declaring one nation more mature than another. “Transition” normally means the capability exists but its integration route is changing.
Established stable current routeTransition target route changingMixed national and local mechanisms coexistGap / unclear public evidence does not establish a general route
| Capability | England | Wales | Scotland | Northern Ireland |
|---|
4. Data-flow explorer
Select a capability to compare the actual route taken by the information. This view is intended to prevent the common mistake of treating “supports FHIR” as equivalent to supporting the clinical flow.
5. Cross-border implications
Fact
Identity is nationally scoped
England and Wales are NHS-number centred, Scotland uses CHI, and Northern Ireland uses the Health and Care Number supported by NIDIS. Cross-border and multi-jurisdiction architectures should therefore preserve assigning authority and identifier provenance rather than assume one universal person identifier.
Analysis
The common layer should be semantic, not infrastructural
The viable common denominator is a stable semantic and provenance discipline. The different API, messaging, repository and portal patterns should be mediated explicitly rather than forced into one canonical transport architecture.
Unresolved
External access to encompass needs direct confirmation
Public DHCNI material clearly describes EpicCare Link, but does not publish a public structured integration catalogue comparable with NHS England or DHCW. Any cross-organisational integration initiative should treat the available machine-to-machine route as an early discovery and contractual question.
Practical cross-border flow
Patient presents in another UK nation → local national identity is resolved → available source information is retrieved through that nation's services → provenance and original coding are retained → secondary care records the new episode → discharge/transfer information is returned through the receiving nation's available route.
That is a mediated transfer of information, not a single record moving transparently between four health services.
6. Source register
Primary government and national digital-service sources are given greatest weight. Source IDs used in the matrix link back to this register.
7. Limitations
Unresolved: Public documentation is uneven. England and Wales publish relatively detailed API and integration material; Scotland publishes more target-state programme information; Northern Ireland's public material is stronger on encompass service boundaries than on external machine-to-machine interfaces. Absence of a published API is therefore not evidence that no interface exists.
Scope: This resource compares the integration surface around secondary care across the four UK nations. It does not attempt to catalogue every local Trust, Board or specialty interface, nor does it constitute clinical-safety, cyber-security, information-governance or regulatory assurance.
Currency: National digital programmes change. The resource is dated 13 September 2026 and should be versioned when material national services or onboarding routes change.