Formative Evaluation

Both the FDA and IEC 62366-1 require formative and summative usability evaluations. It is recommended to perform formative usability tests iteratively at different points in development with 1-2 participants per iteration, so that a total of 4-10 participants are tested. Conducting this testing early means that the requirements of intended users can be identified early during development and their implementation can be tested in the next iteration. In case of one-time formative testing, depending on the complexity of the user interface, the participation of 5-15 users with mature prototypes is recommended.

Our Services

We create and execute FDA and IEC 62366-1 compliant test plans for both formative and summative evaluation. This includes:

  • Selecting the appropriate evaluation methods specifically for your product and its risks (e.g. heuristic evaluation, usability testing),
  • Determining the necessary number of test persons and recruiting them, and
  • Defining success criteria, and how to evaluate and document the results. 

We conduct formative tests using these methods, among others:

  • Heuristic Evaluation: Usability experts test the product against heuristics and norms.
  • Cognitive Walkthrough: Usability experts guide representative users through the product to get user feedback.
  • Usability Testing: In a usability test, intended users are asked to perform a real-world task with the product in a real-world usage environment.
  • A/B and Multivariate Testing: Users test two or more variants of the user interface or individual user interface elements.

Contact Us

We are happy to assist you and coordinate the testing effort depending on the approval location (e.g. the US or Europe).


+1 (301) 244 6335


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