Legacy Modernisation for UK HealthTech — DTAC Built In

Clinical Safety During Legacy Modernisation

NHS legacy modernisation is uniquely high-stakes: incorrect data migration can directly harm patients. DCB0129 clinical safety standard applies throughout the modernisation project, not just the final product. Key requirements: Clinical Safety Officer (CSO) oversight of all data migration decisions, hazard log maintained and updated throughout project, go-live clinical safety case completed and approved before any patient-facing cutover.

NHS Data Migration and UK GDPR Article 9

Migrating patient data (special category under UK GDPR Article 9) requires: Data Protection Impact Assessment (DPIA) before migration begins, Data Processing Agreement with all intermediate processing environments (including staging and test environments used for migration validation), and post-migration audit confirming all data transferred correctly and no legacy patient data remains in non-compliant storage.

NHS DSP Toolkit Continuity During Modernisation

NHS DSP Toolkit Standards Met status must be maintained throughout the modernisation period. The new system's DSP Toolkit evidence must be prepared before decommissioning the legacy system. Parallel running period: run old and new systems simultaneously for a defined period to validate the new system's DSP Toolkit compliance before switching off the legacy.

Zero-Downtime NHS Migration

NHS clinical systems typically cannot have planned downtime during clinical hours. Strangler fig pattern: run legacy and new systems simultaneously, route traffic to the new system gradually (starting with non-clinical administrative functions), increase traffic only after clinical validation, and maintain instant rollback capability for the full migration period.

DTAC

UK GDPR Article 9

NHS DSP Toolkit

clinical safety DCB0129

business continuity