Iterative evaluation of your medical device concept
The influence of the user study should be prevalent throughout the design of your concepts and throughout their iteration, with an ever-present team member who is the champion for the end user. The interpretation of the output of the study should be considered and represented to ensure that concepts stay aligned with the needs of the surgeon and continue to address the problems facing them during the procedure.
Once your concepts have been developed into functional concept models, it’s important to test them iteratively with users in their real (or simulated) environment to ensure they solve the challenges you set out to address. As a device developer, you need to ensure that your new device hasn’t caused new problems by solving old ones. For example, if you have designed your device to encourage the surgeon to adopt a less strenuous position when operating, has this had unintended consequences? Can the surgeon still use other systems they use in partnership with this new instrument? Or is it now incompatible?
Some things are hard to quantify, so if you have set out to make the device intuitive or comfortable, you need to validate this. This evaluation should not be on a single concept, but several. User studies take time and cost money, so going to users early on in your development with a single concept will likely yield a binary response – it either is or isn’t intuitive to use. Having several concept variants will aid users to articulate the pros and cons of each concept and enable you to identify what makes a concept more intuitive and which concept, or aspects of your concepts, to progress further. Sometimes, the best device design can be a combination of previous concepts.
As noted, during the user study you should make sure that you are observing the surgeon in a representative environment. This is equally important for testing concept models. However, for the rapid iteration required for early phase concepts, the costs and lead times associated with a user study may be unviable. This is where the development of a rig (custom machinery developed for testing) or use of a specialist laboratory can be extremely useful. Rigs can be specially developed to simulate surgical conditions and enable regular and robust testing of device concepts. If environmental conditions are key to accurately assess your device performance, environmentally controlled labs should also be used.
The combination of this type of testing, in addition to quantitative data capture, is key to the success of your device. Without regular interaction with users and testing in a representative environment, developments can stray and fail to meet their original objectives.