What is Usability?

Usability testing is the evaluation of user interfaces offering products or services by testing accomplished by actual users. Usability testing is a crucial step in the product design cycle since it is the only way to gain insights in behavior, feelings and thoughts of users experiencing and using a product. Ultimately, usability testing is supposed to trigger improvements in user-friendliness, consistency and overall platform “look and feel”. In short, usability testing measures whether certain human-made products serve their intended purpose. Products that can benefit from usability testing are consumer products, foods, websites or web applications, devices, machinery, forms and many more.

What to test

According to usability expert Jakob Nielsen (PhD), usability can be measured in quality components such as learnability, efficiency, memorability, errors, safety and satisfaction:

  • Learnability. How easy can operators complete basic-level tasks when encountering a design for the first time?
  • Efficiency. How quickly can they perform certain tasks once they are familiar with the design?
  • Memorability. Do users remember how to use the design after periods of not using it?
  • Errors. Do the users make any errors? – If yes, how many, how simple or substantial are they and how easy is it to recover from them?
  • Safety. Can tasks be performed in a safe environment or does the product lack safety standards?
  • Satisfaction. Last but not least, how high or low is the user’s satisfaction level when using the products?

However, these are only the most common quality components. Dependent on the type of service or product and desired purpose, you might want to focus on a subset or expand the list respectively.

How to test

Most commonly, in a test setup representative users are asked to perform certain tasks and use the products/designs in a simulated environment which is supposed to be as close to a real-life scenario as possible. From behavioral observations and self-reported respondent feedback the designers can deduct if and to what extent the defined quality components have been fulfilled. In other words, designers extract information on how close the tested candidate is to the desired end-product.

Usability research becomes a lot more powerful when adding biosensors. While electroencephalography (EEG) helps to evaluate motivational patterns and cognitive states (e.g. high or low engagement), eye tracking gives insights about gaze position and eye movements as well as attention, interest and arousal. Galvanic skin response (GSR) on the other hand measures electrical conductance of the skin from body parts that are sensitive to emotional processing and physiological arousal. Additionally, facial expression analysis can be used for more detailed insights into emotional processing as reflected by emotional reactions, e.g., joy, anger, fear, surprise, confusion. These biometric tools overcome the issue that tested respondents generally cannot verbalize  or sense certain physiological, emotional or cognitive states that they are currently in. Biometric research can then be used to add quantitative data and support or disprove their qualitative self-reports.

Why to test

At first glance, usability testing seems sophisticated and maybe even costly. However, the amount of costs that can be saved is tremendous. Take website usability testing and optimization. If website visitors do not find what they are looking for, they will simply leave the homepage and search for the desired information somewhere else. How are visitors supposed to get in touch, state their interest of buy products or services if they cannot even find what they need?

For internal product design, usability helps cut down training budgets and increase the amount of transactions per hour that an employee can perform. For external design one can probably say that any quality component will increase by usability testing. Support and development costs can be reduced, while the competitiveness of a product is improved.

Please contact the team at iMotions if you would like to get started with eye tracking usability testing, or if you would like to integrate biometric research tools to improve data collection and analysis standards.