Good test instructions will strike the proper balance of brevity and detail, reduce the likelihood of bias, and adequately “set the table” for the participant to provide useful feedback.
The researcher or test planner is solely responsible for making sure that the test instructions are:
Clear: Each sentence should represent a single concept or idea. Words should be chosen carefully and tested repeatedly, so that they are likely to be understood the same way by all who read them.
Concise: Instructions cannot be perceived as lengthy. For the remote unmoderated tests you can do at usabilityhub.com, instructions should be limited to only 1-2 very short sentences.
Sufficient: Instructions should establish a realistic expectation about what is going to be presented, and what is expected of the participant.
Appropriate for the test format: A previous post noted that the test format is important for ensuring that the data is appropriate and useful. Proper instructions will indicate the format in such a way that participants will understand what types of data they will be asked to provide.
The goal of the memory dump test is to determine which element(s) stand out in a design. For this type of test, a simple statement about the process that is to occur is all that is required:
“You will have five seconds to view the image. Afterwards, you’ll be asked a few short questions.”
“After viewing a design for five seconds, be prepared to tell us what you recall about it.”
However, this approach will not work for attitudinal tests, which contain opinion-centered questions that require the participant to recall, consider and comment on the design as a whole entity. For this test format, setting the correct expectation in the instructions means putting the participant in the proper frame of mind for delivering opinion-based responses:
“You will have five seconds to view the image. Afterwards, you’ll be asked a few short questions about your general reaction to the design.”
“You’ll see a screen for a few seconds – pay attention the general aesthetic and visual appeal of the design.”
Instructions for target identification tests are a little trickier and reiterate the critical point that it’s all about the research goal(s) and focusing on the one thing per test that you want to learn. Because the focus is on the participant’s ability to comment on one or more specific elements, it’s sometimes it’s necessary to reference the target in the instructions, so that the participant has enough time to view and consider it.
For example, if the goal is to learn about a website’s navigation bar, it is probably better to reference the bar in the instructions, so that the participant will seek out and focus attention on the bar for the full five seconds.
But, be careful — if the goal is to know whether a specific target is easily spotted in a design, it’s better to not reference it in the instructions.