Design Control in Medical Technology – A Foundation for Safe, Effective, and High-Quality Devices

Why Design Control Matters?

Design Control is one of the most important processes in the development of medical devices. It ensures that a product is safe, effective, and suitable for its intended use. Standards like ISO 13485:2016 and regulations like FDA 21 CFR 820.30 require manufacturers to use Design Control as part of their quality management system. In Europe, the MDR and IVDR also demand a structured and well-documented development approach. However, the value of Design Control goes far beyond legal compliance. When applied well, it helps engineers make better decisions, communicate clearly, and control risks from the first idea until the product is removed from the market. A strong system supports innovation because it gives teams clarity, structure, and confidence. Instead of only thinking about “meeting requirements”, organisations should ask: How can Design Control help us develop better products that truly serve users and patients?

What is Design Control in Medical Device Development?

ISO 13485 defines Design Control as a sequence of planned and documented activities. These activities connect requirements, risks, design results, and testing outcomes in a logical way. This structure allows teams to understand why decisions were made and how the final product fulfils all necessary requirements.

Design and Development Planning Under ISO 13485

Every project begins with a design and development plan. This plan describes:

• The responsibilities of team members.
• The required resources.
• The interfaces between departments.
• The project phases and milestones.
• The timing and purpose of design reviews.

The plan is not a static document and should be updated throughout the project as new information becomes available. A flexible plan helps teams stay organised for technical or regulatory challenges.

Design Inputs: Translating User Needs and Regulatory Requirements into Specifications

Design inputs are the foundation of the development process. They include:

• User needs.
• Intended use.
• Regulatory requirements (such as MDR GSPR).
• Risk-related requirements based on ISO 14971.
• Technical, functional, and performance requirements.

Good design inputs must be clear, complete, and measurable. When inputs are well prepared, teams can design with confidence and avoid unnecessary rework.

Design Outputs: Building Traceability from Requirements to Product Design

Design outputs describe the actual design of the product. They include:

• Drawings and specifications.
• Software architecture and code documentation.
• Materials and component lists.
• Production specifications.
• Test methods and acceptance criteria.

All design outputs must be directly linked to design inputs. This ensures the product meets the requirements and that nothing is forgotten. The outputs serve as the basis for manufacturing, testing, and maintenance.

Design Reviews: Managing Risk and Design Quality Across Development Stages

Design reviews are important checkpoints to evaluate progress and identify problems early. Reviews should be performed by a cross-functional team, including quality experts, regulatory specialists, clinicians, and manufacturing engineers when needed. The goals are:

• To detect errors or missing information early.
• To evaluate risks and update the risk analysis.
• To check if changes are needed in the development plan.
• To approve the project to move to the next stage.

Design Verification: Proving the Device Meets Design Requirements

Design Verification answers: “Are we building the product correctly?“. It checks whether the design outputs match the design inputs. Typical methods include:

• Measurements.
• Laboratory tests.
• Inspections.
• Software code reviews.
• Analytical calculations.

Verification is often repeated during development to give teams confidence
that technical requirements are met.

Design Validation: Confirming the Device Meets User Needs and Intended Use

Design Validation answers: “Are we building the right product?“. It ensures the product meets user needs and the intended use. It is performed using real or simulated use conditions. Common methods include:

• Usability testing according to IEC 62366.
• Clinical evaluations or performance studies.
• Testing on initial production batches.
• Simulated use scenarios.

Validation must be finished before the product is released

Design Verification vs Design Validation in Medical Devices

Verification confirms technical correctness, while validation confirms practical usefulness and safety. Both must be fully documented. A product cannot be released without successful verification and validation.

Design History File (DHF): Maintaining Traceability and Regulatory Evidence

The DHF is a complete record of the development process. It contains all documents, tests, decisions, and changes. A well-structured DHF:

• Supports regulatory submissions.
• Helps future engineers understand past decisions.
• Improves communication and reduces the risk of repeating mistakes.
• Provides clear traceability between requirements, risks, and results.

The DHF should be updated continuously.

Integrating Risk Management (ISO 14971) into Design Control

Risk management is closely connected to Design Control. Risks influence inputs, decisions, and testing. Teams must:

• Identify hazards.
• Estimate and evaluate risks.
• Implement and verify risk control measures.
• Update the risk analysis throughout the project.

Change Control in Medical Devices: Managing Post-Market Design Modifications

Products change over time due to new materials, standards, or feedback. Change Control ensures that:

• Every modification and its risk are evaluated.
• The impact on safety and performance is understood.
• Documentation is updated and regulatory approvals remain valid.

Why Design Control and Change Control Must Work Together

Together, they create a complete lifecycle approach from concept to post-market. Every change can affect the original design logic; Change Control prevents the accidental loss of safety or compliance. The process includes:

• Initiation of a Change Request.
• Impact Assessment on design, risks, and testing.
• Verification of Regulatory Impact.
• Design Control Interaction (new verification/validation, DHF update).
• Approval and Final Documentation.

How Design Control Supports MDR, IVDR, and FDA Regulatory Compliance

Under MDR and IVDR, manufacturers must create technical documentation according to Annex II and III. Design Control provides the structure to:

• Demonstrate compliance with GSPR.
• Ensure traceability between risks and evidence.
• Support audits and clinical evaluations.

Common Design Control Challenges and How to Solve Them

Common Challenges:

• Documentation is only created shortly before audits.
• Insufficient traceability.
• Weak communication between departments.
• Change Control is treated as a formality.

Best Practices:

• Integrate documentation into daily work.
• Use digital tools for requirements and traceability.
• Perform regular design reviews with cross-functional experts.
• Update risk analysis whenever new information appears.
• Build strong cooperation between all teams (R&D, Quality, Manufacturing, etc.).

Design Control as a Strategic Advantage in Medical Device Development

Design Control is a mindset that guides teams toward safe products. When supported by Change Control, it improves quality and ensures compliance throughout the product life cycle. By applying it correctly, companies develop devices that are reliable and truly beneficial for patients.

Disclaimer. The views and opinions expressed in this article are solely those of the author and do not necessarily reflect the official policy or position of Test Labs Limited. The content provided is for informational purposes only and is not intended to constitute legal or professional advice. Test Labs assumes no responsibility for any errors or omissions in the content of this article, nor for any actions taken in reliance thereon.