Usability evaluation enables to compare the product vs. similar competitors’ offers, to test its user-quality in an unbiased way and to understand how successfully it meets the predefined characteristics and schedule.
This is the essence of the direct goal.
Usability evaluation based on international ISO standards helps to measure the product’s user-quality so that to ensure its meeting the global standards.
I rely on several ISO standards while conducting Usability evaluations.
For the basic research we apply ISO-9241 standard (Ergonomic requirements for office work with visual display terminals: Guidance on Usability), which measures Usability through Effectiveness, Efficiency and Satisfaction.
To evaluate products aimed at day-to-day use we apply a more expanded evaluation approach by applying an additional standard ISO-20282 (Easy of Operation of Everyday Products: Test method for walk-up-and-use products).
The format of Usability evaluation report completed in line with ISO-9241 standard is regulated by ISO-25062 standard (Software engineering: Software product Quality Requirements and Evaluation: Common Industry Format for usability test report).
The basic parameters applied for evaluation:
- Total Effectiveness
- Time Efficiency
- Total Time Efficiency
- Expert Time Efficiency
- Satisfaction – based on SUS, QUIS, SUMI or CSUQ forms
- Associate Satisfaction – based on vocabulary test
Extra parameters measured during the evaluation:
- Supportability Coefficient – identifies how fully the product supports and user and helps him to cope with errors
- Intuitiveability Coefficient – shows whether the product’s navigation is intuitively clear for the user
Based on the ISO-9126 standard (Information Technology: Software Product Quality Characteristics and Metrics). This standard is the most comprehensive one. It regulates the product’s quality metrics. ISO-9241 standard is only a small part of these metrics.
On top of ISO-9241 metrics, I evaluate the following:
- Functionality – relevance of the product’s potential to TA goals
- Accuracy – helps to identify how precisely the users meet their goals, provided the goals are not clearly defined
- Safety – the feeling of protection the product’s application gives to users
- Learnability – the time required for new users to get accustomed to the product
- Understandability – clarity of the product’s usage contexts and ability of users to describe the product specifics and application options to other people
- Attractiveness – the power of the product’s appeal from users’ standpoint
Further: ROI Usability
Users and Goals | Effectiveness | Efficiency | Satisfaction | Methods