Advancing NHS Legacy Information Management
A Maturity Model Approach for the Cloud-Native Era
Executive Summary
NHS trusts are under increasing pressure to modernise legacy information management, ensuring compliance, interoperability, and readiness for AI-driven healthcare. This whitepaper presents a staged maturity model, adapted for the NHS, to guide trusts from fragmented, rigid legacy data practices to intelligent, cloud-native information management.
Introduction
Legacy information systems—often siloed, reliant on static repositories, or dependent on complex, on-premise architectures—pose significant risks to NHS organizations. These include compliance gaps, inefficiencies, and barriers to digital transformation. The NHS-specific Legacy Information Management Maturity Model (NHS-LIMM) provides a clear roadmap for trusts to evolve their practices.

The NHS Legacy Information Management Maturity Model (NHS-LIMM)
Stages of Maturity
| Stage | Name | Defining Characteristics (NHS Context) |
| 1 | Ad Hoc | No formal archiving program; legacy systems retained indefinitely; unstructured data (e.g., scanned notes); not accessible for digital health or AI. |
| 2 | Tactical | Basic retention for legal (NHS) requirements; minimal metadata; manual access; not integrated with EPR; not usable by digital platforms. |
| 3 | Managed | Centralised archiving with governance; role-based access; data normalization (e.g., SNOMED, HL7); partial integration with NHS digital workflows. |
| 4 | Strategic | Archived data leveraged for clinical, operational, and legal use; feeds NHS dashboards; APIs for integration; procurement includes interoperability. |
| 5 | Intelligent | Archives are AI-ready; data used for advanced analytics, predictive modeling, and digital twins; supports real-time smart care and research. |
Domains and Components
| Domain | Ad Hoc | Tactical | Managed | Strategic | Intelligent |
| Governance & Lifecycle Risk Management | No policies; high risk | Basic retention; limited decommissioning | Formal governance; audit logs | Dynamic policy enforcement; real-time dashboards | AI-driven governance; predictive risk modeling |
| Infrastructure & Interoperability | Flat files; not linked | Proprietary system; limited search; isolated from clinical systems | Structured, searchable; partial EPR linkage | FHIR/HL7 APIs; seamless integration with digital platforms | Embedded in NHS data fabric; NLP / ML enrichment; real-time interoperability |
| Data Utility & Smart Care Enablement | Not used for care | Manual audits only; slow access | Supports reporting and pilots; some workflow integration | Used in decision support and virtual care; real-time data feeds | Trains AI/ ML; supports autonomous tools; enables continuous improvement |
Advancement Criteria
Ad Hoc → Tactical:
Inventory legacy systems; implement basic archive for legal retention; begin standardizing key data (e.g., discharge summaries).
Tactical → Managed:
Deploy centralised, cloud-ready archive with role-based access; normalise data for interoperability; develop access policies for digital/virtual care.
Managed → Strategic:
Enforce access controls; integrate archives into clinical workflows via APIs; ensure queries return patient-centric histories in real time.
Strategic → Intelligent:
Enrich data with AI tools; enable NLP-based search; link archives to analytics and clinical systems; support real-time AI-powered decision support and research.
Implementation Roadmap
Assess
Benchmark current state against NHS-LIMM; inventory systems, workflows, and data sources; rate maturity by domain.
Align
Define strategic outcomes (safety, experience, compliance); secure executive sponsorship; set governance.
Architect
Design interoperable, cloud-native data layers; define APIs with EPR/ERP/CRM; select platforms supporting AI-readiness and rapid integration.
Automate
Digitise manual workflows; implement SaaS-native archiving and policy systems; establish real-time data pipelines.
Analyse
Introduce descriptive to predictive analytics; deploy dashboards; manage to leading indicators.
Orchestrate
Adopt AI-driven workflows (e.g., autonomous data enrichment, dynamic governance).
Sustain
Embed continuous improvement; measure ROI; expand governance to include ethics, bias, and model risk management.
Key metrics & ROI
Time to Data Retrieval:
↓ Average time to locate and access archived patient records or legacy clinical documents (measured in minutes/hours per request).
Data Migration Success Rate:
↑ Percentage of legacy data successfully migrated, normalised, and made accessible in the new archive (target: >99.5%).
Reduction in Legacy System Maintenance Costs:
↓ Annual spend on maintaining, patching, and supporting legacy systems (target: 70–90% reduction post-archive migration).
Compliance Audit Pass Rate:
↑ Number of successful audits with zero findings related to data retention, access, or destruction.
User Satisfaction with Archive Access:
↑ Clinician and HIM staff satisfaction scores for ease of finding and using archived data (measured via periodic surveys).
Support Ticket Volume for Data Access Issues:
↓ Number of IT/helpdesk tickets related to legacy data retrieval or archive access.
Time to Fulfill Subject Access Requests (SARs):
↓ Average turnaround time for responding to patient or legal requests for historical data (target: within statutory deadlines).
Data Quality Improvement:
↑ Percentage of archived records with complete metadata, standardised formats, and error-free migration.
Enablement of Smart Care/AI Initiatives:
↑ Number of digital/AI projects (e.g., predictive analytics, digital twins) leveraging archived data as a foundation.
Decommissioned Systems Count:
↑ Number of legacy applications/silos fully retired as a result of successful data archiving.
Governance & Responsible AI
Establish a cross-functional governance council covering data quality, privacy, safety, equity, and AI model risk. Adopt bias testing, human-in-the-loop review for high-impact decisions, and transparent audit trails. Align policies with NHS regulatory frameworks and embed continuous monitoring into operational dashboards.

How to Use This Model
- Use NHS-LIMM to benchmark your trust’s current state.
- Sequence change from digitizing core workflows to embedding predictive analytics and, ultimately, orchestrating AI-driven, autonomous processes.
- Align leadership on target outcomes and maturity goals.
- Reassess quarterly, celebrate advancements, and reinvest where leading indicators show the most leverage.
Conclusion
By adopting the NHS Legacy Information Management Maturity Model and prioritizing agile, cloud-native solutions, trusts can systematically transform legacy data practices—supporting safer, more efficient, and AI-enabled care. This journey is not only about compliance—it is about building an operational “nervous system” that senses early, learns continuously, and delivers the right action at the right time.


