Hello! We are Xin Wang, Neeley Current, and Gary Westergren. We work at the Information Experience Laboratory (IE Lab) of the School of Information Science & Learning Technologies at the University of Missouri. The IE lab is a usability laboratory that conducts research and evaluates technology. What is usability? According to Jakob Nielsen’s definition, usability assesses how easy user interfaces are to use. With the advancement of Web technology, in the past eight years, our lab has successfully applied a dozen of usability methods into the evaluation of educational and commercial Web applications. The evaluation methods that we have frequently used include: heuristic evaluation, think-aloud interviews, focus-group interviews, task analysis and Web analytics. Selecting appropriate usability methods is vital and should be based on the development life cycle of a project. Otherwise, the evaluation results would not be really useful and informative for the Web development team. In this post, we focus on some fundamental concepts regarding one of the most commonly adopted usability evaluation methods–Think-Aloud protocol.
Hot Tip: Use think-aloud interviewing! Think-aloud interviewing is used to engage participants in activities and then ask users to verbalize their thoughts as they perform the tasks. This method is usually applied during the mid or final stage of Website or system design.
Hot Tips: Employing the following procedures are ideal:
- Recruit real or representative users in order to comply with the User-Centric Design principles
- Select tasks based on frequency of use, criticality, new features, user complaints, etc.
- Schedule users for a specific time and location
- Have users operate a computer accompanied by the interviewer
- Ask users to give a running commentary (e.g., what they are clicking on, what kind of difficulty they encounter to complete the task)
- Have interviewer probe the user about the task s/he is asked to perform.
- When users verbalize their thoughts, evaluators may identify many important design issues that caused user difficulties, such as poor navigation design, ambiguous terminology, and unfriendly visual presentation.
- Evaluators can obtain users’ concurrent thoughts rather than just retrospective ones, so it may avoid a situation where users may not recall their experiences.
- Think aloud protocol allow evaluators to have a glimpse into the affective nature (e.g., excitement, frustration, disappointment) of the users’ information seeking process.
- Some users may not be used to verbalizing their thoughts when they perform a task.
- If the information is non-verbal and complicated to express, the protocol may be interrupted.
- Some users may not be able to verbalize their entire thoughts, which is likely because the verbalization could not keep pace with their cognitive processes–making it difficult for evaluators to understand what the users really meant.