Risk and Design-Control Interfaces
Design control connects what a medical device needs to do with the evidence that its design is suitable. Risk information helps shape requirements, tests, and decisions throughout that work.
This lesson introduces the connections a Quality Manager needs to recognize. Watch for the difference between inputs and outputs, between verification and validation, and between coordinating evidence and approving a technical conclusion. We will also follow a proposed component change beyond the purchasing decision.
Plan the work and its evidence
Design and development is planned and controlled. The plan identifies stages, responsibilities, reviews, verification, validation, transfer activities, resources, and a way to trace outputs to inputs.
Keep the plan current as the project changes. Product-realization planning also includes documented risk-management processes and retained evidence.
Quality coordination helps ensure the activities occur and their records can be found. Technical judgments still need suitably competent and authorized people. Organizing a review is valuable work, but it does not by itself qualify someone to approve every conclusion discussed there.
Inputs describe what is needed
Design inputs state what the product must do and the constraints it must satisfy. They include intended-use needs, safety and usability requirements, applicable regulations and standards, and relevant risk-management results.
Inputs need review and approval. They also need enough clarity to support verification or validation later.
If an input leaves an important expectation ambiguous, the design team may build one interpretation while the evaluator expects another. Clear inputs give the design work and its evaluation a shared basis. They are the starting requirements, not simply a description of the finished device.
Outputs define the design
Design outputs include specifications, drawings, software, and manufacturing information. They describe the design in forms that others can build, evaluate, and use.
Outputs must meet the inputs, define or reference acceptance criteria, and identify characteristics essential for safe use. They need approval before release.
The connection matters as much as the collection of files. A drawing can be complete as a file while an input remains unaddressed. Traceability helps the team see which outputs address which requirements and where evidence or design work is still needed.
Verification and validation ask different questions
Verification asks whether design outputs meet design inputs. Validation asks whether the resulting device meets requirements for its intended use or application.
A bench test against an engineering specification may provide verification evidence without showing that intended users can use the device successfully. One favorable result does not answer every design question.
Plan appropriate methods and acceptance criteria, and retain results, conclusions, and necessary follow-up. Validation must be completed before release for customer use. The important distinction is the question the evidence answers, not simply the name of the test.
Transfer connects design to manufacturing
Design transfer establishes that design outputs are suitable for manufacturing. Sending drawing files to a production team is not enough by itself to establish that result.
The manufacturing information must support realizing and accepting the product as intended. Transfer therefore connects the approved design with the processes and information used to make it.
For the Quality Manager, the coordination task is to help ensure the planned transfer activities occur and their evidence is available. The technical assessment still belongs with people competent and authorized for that work.
Assess a change before implementing it
A design change needs identification, review, verification, validation as appropriate, and approval before implementation. Calling it minor does not establish that its effect is minor.
Consider function, performance, usability, safety, and applicable requirements. Look at component interactions, work in process, devices already delivered, risk-management information, and production processes. The review also considers whether regulatory filings need attention.
A small physical change can affect an important interface or risk control. The decision needs evidence about those effects rather than confidence based only on the size of the change.
Example: a replacement pressure sensor
Imagine a supplier proposes a replacement pressure sensor. It fits the same space and has a similar purchasing description. Those facts do not establish that it is an acceptable substitute.
Engineering reviews performance and interfaces. Risk management considers affected hazards and controls. The team plans appropriate verification or validation and considers whether production or service instructions need changes.
The Quality Manager coordinates the evidence and approvals. That coordination helps ensure the decision is supported, while authorized technical personnel make the judgments within their responsibilities.
Follow the change through the system
The sensor decision also needs to address existing inventory and affected devices already in the field. A change review is not limited to the next purchase order.
The result depends on the evidence and the significance of the change. This lesson does not prescribe a particular product disposition or regulatory action. It teaches the need to recognize the connections and route them to the right people.
Your company's approved procedures define the actual workflow and authorities. A useful coordinator makes sure those connected questions are answered before the change is treated as complete.
What to carry into your work
Follow the links from requirements to design outputs and evidence. Ask what each evaluation actually demonstrates. When something changes, consider the effects across the device and its lifecycle, and preserve the distinction between coordinating the work and approving its technical conclusions.
This lesson draws on the AAMI and ISO practical guide to ISO 13485, sections seven point one and seven point three. The examples are educational. Applicable requirements and your company's approved procedures govern actual work.
SOURCE CREDIT AAMI/ISO 13485:2016 — Medical Devices: A Practical Guide (ISO 2017), §§7.1 and 7.3; purchased through ANSI. This video presents original educational explanations informed by the guide. It is not an official AAMI, ISO, ANSI or FDA course. Applicable requirements and company procedures govern actual work.