Heuristic Evaluation
Key Point
- An evaluation conducted by human factors experts to identify potential usability issues that intended users may encounter when interacting with a product’s user interface.
What are they and Why use them
Heuristic evaluation is a method that allows human factor experts to measure the usability of a user interface based on a predefined list of rules of thumb (the heuristics). There are a number of heuristics that can be used to evaluate a user interface including Nielsen’s, Shneiderman’s, Gerhardt-Powals’, and Connell and Hammond’sNN/g website (10 min read).
When to use them
Like Cognitive Walkthrough, a heuristic evaluation can be conducted at multiple times during the course of development, and as early as sketch prototypes of the user interface. This allows obvious issues to be discovered from low-fidelity prototypes to more nuanced issues that can only be found with a high-fidelity user interface.
How to use them
A heuristic evaluation can be conducted using the following seven steps.
- Decide on which set of heuristics best suits your user interface. Additional heuristics may also be included, depending on the product being developed.
- Work with healthcare usability experts and not potential users. It is recommended that multiple experts, ideally five, are used to ensure that all aspects of the user interface are properly evaluated.
- Briefing session. Ensure that those evaluating the user interface know what is required of them and which aspects of the user interface you want them to evaluate. The information provided to each evaluator should be the same so as not to introduce bias into the evaluation.
- Begin the first phase. This phase is exploratory, allowing the evaluators time to understand the interactions and scope of the product. Then, as experts, they can decide on which elements of the heuristic they want to focus on. Ideally each evaluator will work independently of the other evaluators during this phase.
- Begin the second phase. This phase is for the evaluators to apply the heuristics to the user interface they are evaluating.
- Record the findings. This can be done in one of two ways; firstly, an observer may be used to take notes and possibly record the interactions of the evaluator. Secondly, the evaluator can be left to make their own notes. Having an observer present requires coordination between parties; however, an observer reduces the time required to analyse the data as this can be done on the fly with no need to interpret the evaluator’s decisions.
- Debriefing session. This time is for the evaluators to come together and synthesise their findings to create a complete list of problems. This phase also demonstrates why using usability experts, rather than potential users, is important as the evaluators are not only asked to define usability issues, but also recommendations on how to address the usability concerns. The report should list all identified problems, explain why they are an issue, depict the heuristic that each problem relates too, and provide suggestions to improve the usability of the product.
Pros
Evaluators have the freedom to focus on heuristics they are familiar with. The evaluation can be conducted at the early stages of development. Not only are usability concerns identified, but potential solutions are also provided from healthcare usability experts.
Cons
It can be difficult to find enough domain specific usability experts to evaluate and cover all areas of the heuristics. Some evaluators, who may not be familiar with healthcare, may overshoot the mark and identify issues that would not usability issues for the intended users (e.g., terminology).
Points to ponder
- What aspect of the user interface should be evaluated?
- Do the heuristics you are using cover all elements of usability for your user interface?
- Are the evaluators familiar with healthcare products and user interfaces?
- When in the project is the best time to conduct a heuristic evaluation?
