As Test Analyst, one will design test cases concerning about following quality attributes such as: Accuracy, Suitability, Interoperability, Functional Security, Accessibility and Usability. Here, I would like take some notes about Usability Testing as it’s very common but still abstract for us to practically apply it. The challenge is while usability is common-sense and straight-forward for all testers (and perhaps all people who are using computers), what is the technique to design test cases for it? Is there any guideline or instructions so that we can effective measure the usability of our system?
Definition:
You want to test and measure the capability of your system to be understood, learned, operated and attractive to users when used under specified conditions. At the end of usability testing, you want to make sure that at least your target users are effective, efficient and satisfied with the software.
Understandability:
- The simplicity or difficulty of figuring out what the software does and why you might need to do it. Could you shortly read the manual or just look at the GUI and understand what the software’s supposed to do and why you want to spend time using it?
Learnability:
- The simplicity or difficulty of figuring out how to make the software do what it does. Is it intuitive, easy for you to learn how to use the software? Are there any hints, underlying metaphors which naturally guide to explore the software features?
Operability:
- The simplicity or difficulty in completing your tasks using the software’s feature set. Is it easy, effective and efficient for you to have your tasks done by provided features?
Attractiveness:
- Which is the extent to which the software is visibly pleasing, friendly and inviting to the user?
What you need?
- Knowledge about your target users: their background, working environment, computer literacy…
- Black-box Testing techniques
- Knowledge of sociology, psychology, culture, language and national standards (in plus but very helpful)
What are the techniques?
- Inspection, Evalution and Review: consider system specifications and designs under usability point of view. Actual users could be invited to give comments on mock-ups or demo version.
- Usability test scenarios: measure usability attributes. Testers receive a document including instructions, test procedures, guideline to take notes and log results or checklists. In the test script, there are also questions or checklists which ask users to evaluate the interface, the meaningfulness of messages and outputs.
- Survey or questionnaire: gather observations of users when they interact with the system. There are Software Usability Measurement Inventory (SUMI) and Website Analysis and Measurement Inventory (WAMMI) which provided standardized surveys, questionnaire for usability testing. Unfortunately, these are commercial services so you might want to refer to some of free, sample questionnaire available such as Example to screening questionnaire, Sample SUMI questionaire, Sample WAMMI questionaire… to design a survey for your own needs. Unless there is strict regulation to use standard surveys, I think one has little difficulty in creating usability questionnaire for his/her system. All we need to do is just keep in mind the objective of usability testing and its quality attributes.
Read more:
- Usability Testing Checklist
- [Ebook] Handbook of Usability Testing – download at Vietnamese Testing Board
