Defining a Clear Intended Purpose for Software as a Medical Device (SaMD) in the UK

Why the Intended Purpose Matters

Failure to adequately define the intended purpose of a SaMD impairs compliance with UK medical device regulations. It makes designing a robust quality management system difficult, creates ambiguity in generating sufficient clinical evidence, and hinders effective post-market surveillance. The MHRA views an inadequately defined intended purpose as a potential serious failure to meet essential requirements. Crafting an intended purpose in the context of Software as a Medical Device (SaMD) - GOV.UK

A clear intended purpose supports the entire lifecycle: it informs risk management, classification, clinical evaluation, conformity assessment, labelling, and vigilance activities.

Key Elements of an Effective Intended Purpose Statement

The intended purpose should be clear, specific, and detailed enough to avoid ambiguity. Manufacturers should describe:

• What the SaMD does (its core function and output)
• The medical purpose or health condition addressed
• The intended user population (e.g., patient group, disease stage)
• The intended users (e.g., healthcare professionals, patients)
• How the output influences clinical decision-making or patient care within a care pathway
• Any limitations, contraindications, or specific indications

Including reasonable indications or contraindications and explaining the role in clinical pathways is essential for specificity.

Common Issues and Vagueness to Avoid

The MHRA identifies vagueness in several ways:

• Failing to specify reasonable indications or contraindications for use
• Not stipulating how the SaMD output influences clinical decision-making within a pathway
• Overly broad or unclear descriptions of population, condition, or use context
• Lack of detail on intended users or environment

Such vagueness can lead to misclassification, insufficient evidence, or regulatory non-compliance.

Benefits of a Precise Intended Purpose

A well-defined statement enables:

• Appropriate device classification under UK MDR rules
• Focused generation of robust clinical evidence with clear outcomes
• Effective risk-benefit analysis and state-of-the-art demonstration
• Transparent communication with regulators, distributors, customers, and the UK health system

The MHRA encourages making the intended purpose publicly available to maximise these benefits and support engagement across stakeholders.

Regulatory Context and Implications

The intended purpose determines whether software qualifies as a medical device and its risk class. It underpins all evidence requirements and post-market obligations. Manufacturers should ensure alignment with the UK Medical Devices Regulations 2002 (as amended) and relevant MHRA guidance on SaMD qualification and classification. Crafting an intended purpose in the context of Software as a Medical Device (SaMD) - GOV.UK

This guidance forms part of the MHRA's broader Software and AI as a Medical Device Change Programme to modernise regulation while ensuring patient safety.

Practical Advice

Draft the statement early, refine it iteratively, and ensure consistency across technical documentation, labelling, and promotional materials. Consult MHRA resources or seek advice for complex cases involving AI or evolving SaMD.