So you have a medical device and you want to do formative usability testing, because you have to comply with the IEC 62366, and that’s because your goal is to go to market under the EU MDR (right?). “Cool” (sarcastic chuckle)!
The EU likes to over-regulate medical devices (.. by a lot), but the requirements towards usability are actually rather short and quite sane – things which can’t be said about many other regulatory requirements (cough, SOUP).
For usability stuff, your main work boils down to two things: Doing the summative and doing the formative usability evaluation. Here, we’ll focus on the formative usability testing. To read about the other one, head over to our article here. Also, if you’re wondering what the differences between the two are, there’s another article with a handy table here.
Cool! With that out of the way, let’s look at formative usability testing. I’m sure you’re just excited as I am!
How To Do Formative Usability Testing
The TLDR is “do whatever you want, but make sure to document it”.
That sums up the requirements. If you get distracted easily (like I do), you can now stop reading this article, close this tab and head back over to YouTube (to watch tennis, like I do). Or you could continue reading if you’re interested in more details (like I’m not). So.
The IEC 62366 doesn’t narrow down the method you must use for formative usability evaluation. So it’s up to you. I’ll give you some examples and then you’ll get the idea pretty quickly:
- You get on a video call with someone who is an advisor to your company and also an intended user of the future device to show them your current prototype.
So the idea here would be that you’ve made some progress with your development, you now have something to show (e.g. by sharing your screen on Google Meet or so), and you have some people you regularly ping for feedback already anyway. If you’re developing software for physicians, you might have advisors which are physicians. If you’re developing something for patients, you might be in touch with some patients who are following your development. In any case, reach out, schedule a call, share your screen and take notes. To see what to document, see further below. - You get a “usability expert” (typically a UI/UX person) to review your application.
In other words, someone who knows some stuff about usability takes a look at what you’ve built and gives you some pointers on what you can improve. This type of formative usability testing can be very informal, too: Just give them access, and they should send back a few bullet points on what they think. Document that somewhere in your QMS (hopefully Formwork). Done. - You organize an actual user test with a group of people who are the intended user of your future device.
This is essentially the same like your summative usability testing. That being said, the formative testing doesn’t have the same (hard) requirements, so no need for a minimum number of people, and also no need to do this with your final device (it can be any in-development version).
That leaves the question.. why do a huge user test then at all? I guess I wouldn’t recommend it. Or do it with 1-2 users in a very informal way – you’ll probably get similar insights, for much less effort.
You get the idea. The one-sentence summary here is “you’re showing your device to someone whose feedback might be very useful for you, and you document that”. Very useful, actually (I’m serious)!
Things To Consider
You might have many questions now – let’s go through them one by one.
When To Do It?
Formative usability testing is done while you’re still working on your medical device. This is the big difference between formative and summative testing – formative is meant to be done during development so shape your development, whereas summative testing is mostly to ensure that it actually works and doesn’t harm your users (at least usability-wise).
How To Document It?
You can document it in whichever way you want.
In other words, it doesn’t have to be a video of a video call (or of an in-person meeting). It could simply be a bunch of bullet points in a document, or paragraphs instead of bullet points, you get the idea. You’d just need something to show auditors if you want to show them that you’ve done something for formative usability testing. However..
Is It Mandatory?
It’s not mandatory.
Yes, you read that right. The IEC 62366 doesn’t specify that you must do formative usability testing. Only summative testing is required (= at least once). So you could simply skip this step. That being said, it’s actually quite useful and it can’t hurt to do it at least once (it’s sometimes a bit awkward to say “yo, we didn’t do anything” when an auditor asks you about something).
How Often To Do Formative Usability Testing?
It can be done multiple times.
Contrast this with the summative usability evaluation which, in nearly all cases, is done only once prior to the release of the medical device (or the release of each subsequent version).
