Do’s and Don’ts for Using Biometrics in Your UX Research Projects


Current methods for understanding a user’s emotional response are at best limited, and at worst, entirely inaccurate. As the field of user experience evolves, we need to explore new methods for measuring emotional responses using technologies borrowed and refined from neuroscience and human biology.

Biometrics in UX Research Guidelines  

Here are some do’s and don’ts for using biometrics in your user experience research projects:


  • Hire specialists on your team with a neuroscience, cognition, or experimental psychology background. They will be most helpful during the study design and also during the analysis of your biometric data.  Key Lime has a team of specialists that focus on this area as of September 2017.  
  • Run lots of pilot tests. Incorporating biometrics can add unforeseen challenges to your study and requires extra practice to ensure that data is collected accurately with actual participants.
  • Ensure that you have a sufficient sample size. Biometric studies require more participants than a typical usability test to account for the potentially large variability between participants. You will also encounter more situations where data needs to be excluded because due to improper equipment calibration, equipment failures, etc.


  • Examine biometric data in a vacuum. It is important to triangulate data across a combination of different methods including nonverbal observations, participant retrospectives, surveys & rating scales.
  • Assume that your data is perfect. Measuring biological and neurological responses, especially with the tools accessible to UX researchers, is not going to be 100% accurate. I would recommend looking at general trends in valence (i.e. positive/negative spectrum of emotions) changes instead of trying to pinpoint exact moments where very specific emotions were felt.


Biometrics Questions & Answers

Here are some of the most common questions with some initial thoughts:

 Do participants mind wearing all of that equipment? Does anyone complain about it being uncomfortable?

Before making any purchases, we heavily researched all of the existing hardware currently available to make sure that it was as minimally intrusive to participants as possible. In many cases we are only using one or two measurements at a time. We try to use only one measurement that requires physical contact with the participant, such as wearing a GSR wristband combined with facial analysis that only requires a webcam. At the end of a session we always ask the participant whether wearing any of the gear was uncomfortable for them or if it impacted their experience at all. Most say that once the session begins they quickly forgot that they were wearing anything.


Is it [biometrics] worth it? Wouldn’t it just be easier to interview an individual or give them a survey to complete?

We are at the very beginning of an exciting journey to uncover more about how our users are actually feeling. Biometrics is definitely not for everyone, and it is not a useful endeavor for all situations. The tools and software continue to get better every day, and will likely become more useful to UX researchers within the next few years. However, for those who are very serious about obtaining objective, quantitative measurements about your user’s emotional journey, I would recommend trying out these tools to see if they are useful for your team.

I’m very interested in learning more about biometrics! How did you learn about this topic? Would you recommend any resources?

There really isn’t one place to find out everything you would want to know. Biometrics is still a very new topic for the UX community and most of the resources out there are geared for people in the fields of human biology and neuroscience. Start by reading academic papers to understand how to collect and analyze the data. There are a few worthwhile articles in the ACM Digital Library that provide case studies where biometrics were used in the context of human-computer interaction. I would also recommend looking into each biometric and neurometric measurement (e.g. EEG, GSR, etc.) individually. You can get a basic sense of how these tools work by visiting the websites of the device hardware and software manufacturers. 

Still not sure what is biometrics, click here to read more about it.


READ MORE: Biometrics: What is It?, Why You Should Use Eye-Tracking for Website Optimization, Choosing the Right Survey Tool for Quantitative UX Research, Planning a Better Usability Study , Global UX Research: How Do We Get the Most Out of Research in New Markets?, Outstanding UX Research Naturally Leads Us to UX Design



More by this Author


Add Comment