The purpose of usability testing is to observe user interaction with a product and identify any problems that would prevent it being used safely, efficiently and effectively. In medical device testing the overriding concern is patient safety given that injury and potentially death can result from errors in device design, of significant importance, is the interaction between the user and the device. By understanding more about design and how people use such devices, medical errors can be reduced, thereby saving lives.Usability testing is a critical component of new product development in the medical device industry. In its simplest form, it is the process of understanding how easily your target audience find it to use your product or service. It typically consists of test sessions which allow physicians, nurses, therapists, technicians and patients to trial medical devices and deliver feedback, to ensure no design detail is missed and “no stone is left unturned” in the development process.
Usability testing has its raging battle going on between formative and summative testing. The armies are divided between these two types of usability testing and for good reasons. Both formative and summative tests are so widely different that an argument on which one is more necessary is bound to break out. So which one is more important during the development process? The only way to know is to compare and understand the differences between the two kinds of tests. But before that, let’s take a look at what formative and summative testing means.
Introduction to Usabilty testing
Formative vs Summative Usability
Formative or qualitative user testing
Conducted with a team of 5-7 users during the design stage of the device, formative testing is done mainly to design a good user experience for your product. The data collected during formative user testing sessions is observational in nature and deals with the quality of the design, hence the name qualitative usability testing. answers the why and how questions of the design usability. This testing is performed during the initial stages of the design process and the questions it answers is basically why something is not working. When the users performing the test get stuck when performing an action, they look for the reason why the design is not working, and upon finding the reason, find the solution to fix it.
Summative or quantitative testing,
Summative user testing is done after the product has been put into production. Conducted by a group of more than ten testers, the data collected is more about the quantity than the quality of the design (as in, what is the percentage of the users who could use the product without running into a roadblock?), and that is why another name for summative user testing is quantitative user testing.
on the other hand, answer the question regarding how many or how much. Quantitative testing is performed among a large number of users and the data collected evaluates the design usability of the product. With Summative study, the development team can find out what percentage of users had trouble performing a certain action on the platform. This statistical data helps them to redesign the platform according to the user needs.
Even though both Qualitative and Quantitative data are collected to determine whether the design elements are working or not and how they can be improved, the different usability tests are conducted differently so that they answer to different questions.