ANSWER

Usability testing is conducted in different ways over the software development life cycle:

• Usability exploration is performed in the very early stages of software design. The objective at this stage is to establish basic design (‘look and feel’) and navigation decisions, to fit the needs and characteristics of the system’s end-user community. These requirements and decisions form the basis of the user interface design standards that will guide all subsequent design and development. The exploration is typically led by a business analyst or usability expert, working in collaboration with designated end-user representatives.
  
• Usability assessment is performed as part of unit and system testing as software is developed and released. This iterative approach enables detection and correction of errors or problems early in development, to minimize the amount of resulting redesign and re-development. The assessment checks for fulfilment of usability requirements, as well as adherence to user interface design and presentation standards. It also includes assessment of heuristics such as learnability, appropriateness of error messages, efficiency of use, degree of user control, and organization of information. The assessment may be performed by business analysts, quality assurance testers or usability testers.
  
• Usability testing is conducted at key development checkpoints, and may be part of an iterative user acceptance testing approach. It consists of systematic, realistic scenarios performed by end-users, who are guided and observed by business analysts or usability experts. Observations provide key information such as number of errors made, ability of end-users to recover from errors, number of steps or keystrokes needed to complete standard tasks, and how easily users can complete basic tasks without explicit instructions or training. Testing sessions can be supplemented with pre- and post-testing surveys to gather user input and feedback.
  

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Sandy Lambert
Business Architect
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