Zen and the Art of Design Controls

Feb 4, 2015 | Qualification & Validation, Quality + Regulatory

There are days when I think “is it me?” Especially when it comes to appreciating Quality Systems. I confess I do like logic and I even get a buzz when I see a logical progression in project deliverables, moving from A to B to C and so on. It’s wonderful, having links and traceability.

I must make it clear I have never been part of a Quality Department. I have been involved in medical device development for many years and lived through, what I now think of as the unenlightened times (although immensely fun), when we defined our own ways of working, prior to the introduction of Design Controls and ISO 13485; having standards and guidance is now quite comforting for me. This probably explains why I find it distressing when I come across people who do their level best to ignore or get round the logical order laid out in Design Controls.

I struggle to grasp why it is faster to go from A to C and then back to B and then try to jump to D. Worse Tortoise and Hareyet are those who think they can start at C and miss out A & B, until they reach stage F. I have experienced this in various guises and I don’t think I have ever seen a project delivered anywhere close to the original time lines when run like this, usually missing the mark by several years.

Hind sight is a wonderful thing and yes I have on occasion been known to fall back on it, having been carried along with the fast track idea. However, when it comes to building up a sound development package, skipping through stages invariably comes back to bite you if you choose to miss bits out.

Filling documentation gaps that should have been produced much earlier in a project is always fun.

No, I am lying, it really isn’t.

If you have ever had to do this you’ll know that you find out why your project hasn’t gone as swimmingly as you had hoped it would (back to that pesky hindsight thing). Here are three real life examples:

  • Producing the User Requirement Specification for a product when the product design is already decided and having the realisation that the wrong (unjustifiable) features have been added or that critical features are missing from the design is always a hoot.
  • Completing a design FMEA and dreaming up a raft of new and impossible to execute tests after all of the Verification testing has finished.
  • Finally a personal favourite, conducting usability studies with no idea; who the target audience is, what their requirements are or how the device is intended to work.

There has been much in the press lately about the brilliance of 3D printing and undeniably it is fantastic what can be achieved. But there is a flip side; 3D printing has made the possibility to jump around Design Control stages even easier. Designers can now generate what looks like a finished product before anyone else has even had the chance to think about what the problem is that the development team are trying to solve.

It is all too easy to focus on refining or “optimising” this nearly finished product. Contrast this with concepts presented as block models, sketches or simulations. There’s an inherent understanding that much work lies ahead to turn the best concept into a fully fledged, marketable device.

Design Controls CascadeThere are many graphics out there that try to explain Design Controls. The one thing they have in common is that; to get a good output you need a good input, to get a good input you need a good understanding of the problem you are solving.  For me following the flow of Design Controls takes away a lot of development pain and anguish of trying to guess what comes next.

Design Controls is basically a logical progression built from the years of knowledge of other people who have already suffered in development limbo and have found a clear, signposted way through.

“Begin with the end in mind”
Stephen Covey

Look out for our post later this month that may help you think about the point of each stage in Design Controls, enabling you to get the most out of each stage of development.