Design Verification – Medical Device Designed Correctly

Design Verification and Design Validation are the keys to ensuring a successful medical device product. Anyone who has worked with me knows my passion for Design Controls (we formed an entire medical device software company around this!).

It’s difficult to pinpoint and identify the most important of Design Controls. I mean all are important to medical device product development. I can make an argument for each Design Control element.

User Needs establish the scope of the medical device product development project. User Needs define what the end-user expects from your product.

Design Inputs establish all the requirements of the medical device. What it is supposed to do, how it is to perform.

Design Outputs describe how to build the medical device.

Design Reviews ensure throughout your project that all aspects of Design Controls are being addressed.

Design Transfer helps ensure that your medical device is transferred from product development to manufacturing.

Yet, I truly believe that there are two Design Control elements that tie a big bow around your entire medical device product development process–Design Verification and Design Validation.

Design Verification & Design Validation tie it all together

Design Verification & Design Validation tie it all together

Design Verification demonstrates that you designed the medical device correctly. That your product is safe.

Design Validation demonstrates that you designed the correct medical device. That it works as expected.

In this post, I will go into more depth about Design Verification.

Design Verification – proof you designed correctly

By definition, Design Verification demonstrates that your medical device Design Outputs meet the Design Inputs.

The classic Design Control waterfall image (shown above) shows the relationship quite well.

When most of us think about Design Verification, we tend to think about testing. What tests do you need to do to prove outputs meet inputs?

Testing is part of Design Verification

Testing is part of Design Verification

Yes, testing is part of Design Verification. But there are other methods that can be acceptable too, including inspection and analysis.

It’s less important that you worry about the exact Design Verification method. Rather, you should choose the method that makes the most sense for the particular Design Output / Design Input relationship you are evaluating.

Often times, testing is the best (and maybe only) means for a particular Design Verification activity.

Remember that your purpose with Design Verification is to prove you designed the medical device correctly. “Proof” requires objective evidence (documentation).

Design Verification starts early in a project

If you follow the order of operations as defined in Design Control regulations, and as depicted in the waterfall diagram, you might be setting yourself up for disaster.

What I mean by that last statement is this: Design Verification needs to be considered very early in a medical device product development project.

Design Verification really should start at the point when you are defining all those Design Inputs for the medical device you are about to develop.


When defining Design Inputs, you should start to consider how in the world you are going to prove them.

I’ve done it both ways throughout my career. Early on, I didn’t pay any attention to Design Verification when capturing Design Inputs. And then when I got to the Design Verification stages of the project, I often times put myself in a very difficult position. Some of the Design Inputs were damn near impossible to prove.

I quickly learned.

Considering how you plan to verify the medical device when you are establishing the product’s requirements is key.

Doing so will help you write better Design Inputs.

Doing so will help you help you figure out what you already know about your medical device and what you need to find out.

Doing so will be important to project management and the schedule for the project. This will also help you with Design Verification Planning.

Planning Design Verification

Again, you can wait until you approach the Design Verification stages of your medical device product development project to begin planning verification activities.

Or you can start earlier.

Design Verification is more than just the tests, inspections, and analyses you perform to demonstrate your Design Outputs meet Design Inputs.

You should define a plan of attack.

When you start planning Design Verification, your first objective is to figure out what types of verification activities are required, what methods you plan to use, who will conduct Design Verification, how many prototypes / devices are required, and so on.

You may find it necessary to establish formal Design Verification protocols.

Evolving Design Verification Plan & Methods Throughout

Thinking about and starting Design Verification planning and defining methods early in a project are important for another reason too.

As your medical device evolves and navigates through the product development process, you have a chance to do some informal tests, inspections, and analysis on your medical device.

Basically, you can start the process of proving you are designing the medical device correctly before entering into Design Verification.

That way when it is finally time to conduct the formal Design Verification activities, you should have high confidence that your medical device will demonstrate that your Design Outputs meet your Design Inputs.

Design Verification is crucial for regulatory submissions

Remember, too, that there is a pretty good chance that you might have to submit a 510(k) or compile a technical file for your medical device at some point before going to market.

Design Verification is a pretty important aspect of regulatory submissions. Regulators will look for the proof and objective evidence that your medical device is safe and meets all requirements.

This is the essences of Design Verification.

Yes, Design Controls are even important for Class I medical devices

But what if your medical device is class I? Do you need to worry about Design Controls or Design Verification?

Okay, technically speaking FDA does not require Design Controls for most class I medical devices in the U.S.

Other markets, such as EU are a little different. Class I devices outside U.S. are still expected to have a technical file.

I’m a BIG advocate for going through Design Controls for class I medical devices regardless.

To me, it just makes great business sense.

Do you want some assurances to prove that the class I medical device you are bringing to market is safe and effective? Design Controls are intended to do just that.






Jon Speer has been in the medical device industry for over 16 years. In 2007, Jon started Creo Quality to help medical device companies with project management, quality systems, and regulatory submissions. As a result of his experience in the medical device industry, Jon had an idea to develop a software solution to improve how companies handle Design Controls. Because of this was born. You can find him on Google+Twitter, and LinkedIn

Related Posts

No Comments Yet.

add new comment