In this series of posts, we’re taking a look at the recently published final version of CDRH’s guidance “Applying Human Factors and Usability Engineering to Medical Devices”.
In part 1, we looked at both the Human Factors Engineering process and Risk Management and Human Factors, two of the key topics covered by the Center:
- Human Factors Engineering process
- Risk Management and Human Factors
- Design Verification
- Summative Human Factors testing
- Changes to products already on the market
- Human Factors Engineering Summary report
Lets look at how the topic of Design Verification may impact what you’re either already doing, or plan to do.
Design Verification has vanished from a Human Factors perspective – probably a relief for device development teams who were scratching their heads about what was needed in addition to Design Verification as described in ISO 13485 and 21 CFR §820.30 Design Controls.
So now, we can focus on Design Verification being all about confirming that the design outputs (i.e. the device design and associated specifications for performance and attributes) meet the design inputs (what you wanted the device to be able to do). It’s about physical evaluation and testing of devices to confirm, for example, that the force required to turn a dial meets your specification limit. To confirm that the robustness and mechanics of your design function as intended.
Now that might sound straightforward, just get some sample devices from (pre-)production and test them, right?
Design Verification tests shouldn’t be “tick box” tests. Sadly, that’s often what is done by way of Design Verification, however this misses the fundamental point of verifying the design – to confirm that the device performs as required, throughout the range of your specifications. Design Verification demonstrates that devices manufactured/assembled with components from all across your specified ranges actually do work together, and more than that, they work as intended. Verification shows that your “design envelope” works in practice. It also gives you reasonable confidence that, when your manufacturing and assembly processes vary (within your specification) which they will do, the end product is safe to place on the market. And in the long run, that should mean less surprises.
Certainly, the scale of Design Verification can vary hugely, depending upon the number of components, their manufacturing process variability and so on. But it doesn’t need to be a big deal.
You need to be able to rely on the results of Design Verification
Taking care to plan, design and execute DV is a great step on your journey to getting your product on the market. Consider how you will know you can rely upon the data that are generated and analysed.
We’re often asked whether test equipment need to be qualified and test methods validated? You could take the approach of using development equipment and test methods that are not yet optimised. How will you be able to show, to your board and investors, that DV is truly representative of production data?
The long and the short of it is;
- Qualify your test equipment before using it for DV,
- Optimise and then validate the test methods you plan to use during DV.
Take both steps and you’ll have a high degree of confidence that the results you get are translatable to production and routine inspection situations. And there’s the added bonus that you would have needed to do the work anyway during industrialisation and launch preparation.
Spare yourself the nightmare of discovering at that late stage that there was a critical issue with the way you planned to release batches of product onto the market.
When is the guidance effective?
You will have some time to assimilate the requirements…
A whole 6 weeks, as they go live on 3 April 2016.
How will the changes will affect your product development?
What impact they will have upon your Human Factors Engineering programme?
Get in touch today to discuss how you can best navigate the changes and emerge with a Design Verification programme that is “just right” – you know, “fit for purpose”.