Measuring Usability
There is a range of metrics available to help you measure your design improvements. There are numerous measures that can help you find out if your improvements made your Web site:
- More efficient for users
- Easier to learn
- More satisfying to users
Usability is typically measured by conducting usability testing. Learn About Usability Testing.
Factors Measured
The most common factors measured in usability testing include:
- Effectiveness: A user's ability to successfully use a Web site to find information and accomplish tasks.
- Efficiency: A user's ability to quickly accomplish tasks with ease and without frustration.
- Satisfaction: How much a user enjoys using the Web site.
- Error frequency and severity - How often do users make errors while using the system, how serious are these errors, and how do users recover from these errors?
- Memorability - If a user has used the system before, can he or she remember enough to use it effectively the next time or does the user have to start over again learning everything?
Data
There are two types of usability metrics that can be captured during a usability test. These metrics include:
- Performance data (what actually happened)
- Preference data (what participants thought)
Using the Data
Once you gather the metrics, you can use the data to evaluate the usability of your Web site and make recommendations for improvements.
- Conducting a baseline or benchmark usability test (usually conducted before design changes are made on your current Web site).
- Implementing recommendations based on the usability test and improving your current Web site to fix usability issues.
- Re-testing your Web site after the design improvements to measure the effectiveness of your improvements.
