An Introduction to Usability Testing and How to Prepare One
We cannot predict exactly how someone will use a given interface, which is why testing becomes an important phase in any project.
What is a usability test?
Usability tests refer to the evaluation of a product or service by testing it with representative users. It generally involves observing people as they attempt to complete tasks given by the test moderator.
Usability studies allow us to collect qualitative behavioral data, as well as learn about cognitive behaviors and patterns.
The importance of testing
We cannot predict exactly how people will respond to an interface without first testing it. Usability tests allow teams to identify, prioritize and fix usability issues before launch.
The sooner problems are identified and fixed, the less costs there will be, the better the experience will be, and the less impact it will have on development time.
Planning - What you will need
Define objectives and start a research plan
Determine the format and direction of the study
Determine and recruit participants
Write the test tasks
Do a first pilot test
Decide on metrics and success criteria
Motivate other people on the team to observe
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Determine what you want to learn, identify the questions, concerns, and the objectives of the test
Example: Will it be easy for users to find the library's opening hours?
Don't commit to too many objectives in a single study.
Determine the study format
Tests can be conducted in a lab or in context. In addition to choosing the location, you will need to set a time for each participant and have an organized schedule.
Moderado ou não moderado
Moderated tests tend to provide more valuable insights and opportunities due to their nature. You can also complement them by asking questions or reminding participants of the think aloud protocol.
Em pessoa ou remoto
Generally and whenever possible, studies should be conducted in person, as it is possible to analyze more data, namely body language. However, with remote opportunities, it is very common to opt for remote testing using tools such as Zoom, Lookback, etc.
Determine the number of users
According to Jakob Nielsen, 5 users should be sufficient for a usability test. Not to be confused with contextual interviews where this number is different.
5 users discover on average 75% of the most serious usability problems. It is preferable to conduct several studies with 5 people rather than a single study with 20 participants.
Don't forget to recruit one or two extra people to account for those who may not show up.
Recruit the right participants
The best insights come from obtaining feedback through real users. Therefore, it is preferable to recruit the most representative users possible.
Write tasks according to the test objectives
In a usability test, people are invited to complete a series of activities while using an interface, product or service. These activities or tasks are generally written within scenarios and fulfill the study objectives.
Writing contextual and realistic tasks is essential for conducting a valid usability test.
Use exploratory tasks to learn more about behavior
Exploratory tasks allow you to learn how people discover or explore an interface without giving them a specific direction to accomplish.
Example: You are interested in booking a holiday for your family. See if you can find anything useful on this website.
In more quantitative tests or to validate flows, specific tasks can be used:
✅ Good example: Find the opening hours of the municipal library.
❌ Bad example: Find the contacts page.
Decide which metrics to collect
The time needed to complete the task, degree of satisfaction, success or error rate, and the number of errors are some of the most common metrics.
Run a pilot test
The pilot test helps refine the details of some tasks or your script. It also helps you validate the feasibility of what you are planning to do and estimate the time it will take.
These pilot tests can be even more critical when it comes to unmoderated remote tests.
Let's test!
We're ready to start testing and validating our path. 😎
And don't forget to bring a team member or the client themselves, if that's the case. There's nothing better than having stakeholders watch real users interact with the product.