Typically user testing involves a sample size of 3-5 users and should be kept to a few tasks as to not overwhelm the user.
When should user testing begin?
The simple answer is early in the process of creating, modifying or envisioning of a product’s interface.
Often testing begins at the drawing stage and is called paper prototyping. The reason for this is that is allows you to create and test user interfaces quickly and cheaply. It’s easier to change a prototype than the final design.
User testing typically involves a set of users with different levels of familiarity with the product or concepts that the product will solve for. This allows the person testing the interface to gain quick insights and reduce complexity of the tasks being accomplished by the users at various levels of product engagement.
How does paper prototype testing work?
Paper tests are basically the same as other levels of testing and involve the user providing insights verbally using what is called Think-Aloud Protocol. During this process the user is presented with a series of low or high fidelity images on paper and asked to vocalize what they are thinking as they preform a series of basic tasks.
Test often begins by qualifying the user being tested through a series of basic questions followed by the user being given a task (typically written on a small piece of paper) and asked to read it out loud. Using a pen or other device to point at the user will work their way through the task while thinking out loud.
When an interface element is being tested and multiple variations of a solution need to be tested for it is important that each be presented with only one of the potential solutions being tested. The reason for this is to assure clear results and not lead the person being tested into agreeing with the testers P.O.V.
This video shows what typically happens in a user test using a low fidelity paper prototype
How Often Should User Testing Happen?
Not all projects start with paper prototyping and may start later in the process for this reason testing should be done at various benchmarks along the development process. Insights can occur at any step.
Often the order of these steps, which steps are included or the direction taken depend on methodology/need and time frame of the project deliverable.
- Low Fidelity Paper Prototype (hand drawings)
- High Fidelity Paper Prototype (black and white)
- On Screen Interactive Prototype (Balsamic / Axure)
- On Screen Full Color Prototype – (Still images, Interactive, Beta)
It’s amazing how often something as simple as changing a color of a button can completely change the complexity of completing a task.
A task-based think-aloud protocol, which asks users to communicate their thought processes verbally while they work. We ask them to vocalize what path they take to find information, what questions they have, and what surprises or confuses them as they go through the application. We keep questions open-ended and neutral, such as “What do you mean by that?” or “What did you expect to happen?” When users identify a problem, we will ask them how they would fix it. We will observe body language and facial expressions as well.