Subjective Measures of User Satisfaction
These test measures use standard questionnaires for evaluating user satisfaction. Chapter 8 in Sauro and Lewis summarizes the leading measures and their issues.
Properties
- Questions have already been validated with a large sample of users
- Usually rely on scaled answers (e.g. 1 through 7)
- Produce a score summarizing user satisfaction or multiple scores summarizing multiple components of user satisfaction
- Post-task questionnaires (e.g. SEQ) versus post-study questionnaires (SUS)
Issues
- Reliability. Are the scores consistent? Cronbach alpha measures consistency across questions.
- Validity. Does it measure what it is intended?
- Time. How long does it take a user to complete the questions?
Discussion
- How do people map their opinions to a scale number? One Model.
- How can scale scores be summarized and compared? Mean? Median?
- Should questionnaires mix positively worded questions and negatively worded questions?
Articles with survey questions:
In addition to chapter 8 in Sauro and Lewis, the following articles present questionnaires:
- J. R. Lewis (1995). IBM Computer Usability Satisfaction Questionnaires: Psychometric Evaluation and Instructions for Use. In addition to presenting questionniares, this article discusses the issues noted above.
- Chin, Diehl and Norman (1988). Development of an instrument measuring user satisfaction of the human-computer interface
- Measuring Usability With The System Usability Scale (SUS)