Assembling the Technical File for an AI Medical Device

Assembling the technical file for an AI medical device is a critical step in demonstrating regulatory compliance with MHRA and EU rules. The technical file must contain sufficient information to support the clinical evaluation, risk management, and conformity assessment processes. The file must be accurate, complete, and clearly structured to allow regulators to assess whether the device meets applicable requirements.

Content Requirements for the Technical File

The technical file must include documentation that reflects the design, development, and validation of the AI software. This includes data on the clinical data, risk analysis, software architecture, and validation processes. The file must also contain evidence of conformity with relevant standards such as ISO 13485 for medical device quality management systems and ISO/IEC 42001:2023 for AI management systems.

• Software design documentation including architecture diagrams, data flow models, and algorithm descriptions
• Validation and verification records such as testing protocols, test results, and traceability matrices
• Documentation of clinical evaluation including clinical data sources, clinical investigations, and clinical evidence
• Risk management file with hazard analysis, risk assessment, and risk control measures
• Technical documentation of the software development lifecycle including version control, change management, and audit trails

AI-Specific Technical Documentation

For AI medical devices, special attention must be paid to data governance, algorithmic transparency, and explainability. The technical file must demonstrate that the AI system was developed using appropriate data, that the data was representative and unbiased, and that the model was validated against clinical use cases. The file must also show that the AI system meets the requirements of the EU AI Act, particularly regarding prohibited practices and transparency obligations.

• Details of data sources, including data collection, curation, and preprocessing steps
• Information on model training, including training data composition, model architecture, and training parameters
• Validation results including performance metrics, clinical validation data, and clinical utility assessments
• Documentation of explainability and interpretability features, such as feature importance or attention maps
• Records of AI governance, including data protection impact assessments and AI risk assessments

As of 2 February 2025, the EU AI Act’s Article 5 prohibits certain AI practices, such as social scoring or real-time biometric identification, which must not be used in medical devices. The technical file must reflect that these prohibited practices have not been incorporated into the AI software. Additionally, Article 4 AI literacy duties apply from the same date, requiring that staff have appropriate training on AI systems. The file must include records of such training or evidence of AI literacy frameworks.

By 2 August 2026, national supervisory authorities must begin enforcing AI-related regulations. The technical file must be ready to support these efforts. The file must also reflect compliance with Regulation (EU) 2026/1744, which defers high-risk AI obligations to 2 December 2027. The file must indicate that the device meets these future obligations or that a plan exists to meet them.

ISO/IEC 42001:2023 provides a framework for AI management systems. The technical file must demonstrate that the AI software was developed and maintained according to this standard. The file must also include records of any certification or audit activities related to AI governance. The first UKAS-accredited certification body for this standard was BSI, which became operational on 15 January 2026. The file must reflect any such certification or audit outcomes.

For generative AI systems, the technical file must include machine-readable marking by 2 December 2026, as required by Article 50 of the EU AI Act. The file must also show that any such systems placed on the market before this date have been updated to meet these transparency requirements. The file must include records of any such updates or remediation efforts.

Finally, the technical file must be maintained as a living document. Changes to the software or clinical use must be reflected in the file through updates to clinical data, risk assessments, or validation records. The file must also be reviewed and updated at least annually or whenever significant changes occur. The file must be accessible to regulatory authorities upon request, and must be stored securely to prevent unauthorised access or alteration.