--- title: "How to Use Expert Evaluation Correctly" url: "https://www.insideuxdesign.com/en/blog/how-to-use-expert-evaluation-correctly" language: "en" description: "Cognitive walkthrough and heuristic evaluation: what expert evaluation can do – and how to use it right without replacing real user testing." published: "2023-12-23T09:00:00+01:00" updated: "2026-10-14T09:50:32+02:00" --- # How to Use Expert Evaluation Correctly Cognitive walkthrough and heuristic evaluation: what expert evaluation can do – and how to use it the right way without replacing real user testing. There are lots of different usability evaluation methods. One of the most popular is expert evaluation. There are many reasons this method is used so often: first, expert evaluation doesn’t require any research infrastructure. On top of that, it delivers results very quickly and doesn’t depend on test participants. Another advantage is the relatively low cost of running the usability evaluation. An expert evaluation is done without tools, needs little preparation, and is very easy to carry out. So what exactly is an expert evaluation? The answer is very simple: an independent specialist puts themselves in the user’s shoes as well as they can and assesses the system being evaluated. In the UX industry, two expert evaluation methods have become established: heuristic evaluation and the cognitive walkthrough. I’ll take a closer look at each of them now. ## The Cognitive Walkthrough: Put Yourself in Your User’s Shoes The cognitive walkthrough is a task-based approach. The expert puts themselves in the user’s position to play through the most common and most relevant use cases from the user’s perspective. A prerequisite for this method is that the target audience is known and that the expert can actually empathize with it. Tools that help achieve this include personas, empathy maps, and the questions defined by Spencer (2000): 1. Will the user know what to do at this step? 2. If the user does the right thing at this step, will they know that they did the right thing and are making progress toward their goal? With this method, the analysis of usability problems is based on the expert’s general knowledge of usability problems, on their ability to put themselves in the customer’s shoes, and on their knowledge of the customer. If the following questions can be answered with yes, a cognitive walkthrough can deliver good results. - Does the expert have enough usability expertise to recognize problems as such? - Is the target audience clearly defined? - Have personas, empathy maps, etc. been created? - Is the expert able to put themselves in the target audience’s shoes? - Is the expert independent? That last point in particular is very important. Is the expert biased because they have to justify any changes to their boss, or because the changes would mean more work for them? Then the expert may be subject to serious cognitive biases that hurt the quality of the test results. By the way, this problem exists in pretty much all usability testing. ## Heuristic Evaluation: The Standardized Usability Test Unlike the cognitive walkthrough just described, heuristic evaluation is a guideline-based approach. It relies on criteria catalogs such as the guidelines by Nielsen and Molich (1994) or the standard DIN EN ISO 9241-10 (1996). Nielsen’s 10 heuristics look like this: - **Visibility of system status:** The system should always keep users informed about what’s going on, through appropriate feedback within a reasonable amount of time. - **Match between the system and the real world:** The system should speak the user’s language – not with system-oriented terminology (Error 303xxx23Fea), but with words and phrases the user actually understands. Information should appear in a logical order. - **User control and freedom:** Users often choose functions by mistake and need an “emergency exit” to leave the unwanted state. That’s what the system’s or browser’s “Back” function is for. - **Consistency and standards:** Users shouldn’t have to wonder whether different words or actions mean the same thing everywhere. That’s why conventions and standards should be followed. - **Error prevention:** Even better than good error messages is a careful design that prevents errors in the first place. - **Recognition rather than recall:** Objects, options, and actions should be visible. Users shouldn’t have to remember information from an earlier part of their interaction with the system. Instructions should be visible or easy to find. In other words: the system should be intuitive to use. - **Flexibility and efficiency of use:** Users should be able to customize frequent actions so advanced users can work faster. Shortcuts are very useful for achieving a high level of usability. - **Aesthetic and minimalist design:** Dialogs shouldn’t contain irrelevant information that distracts users and buries what really matters. - **Help users recognize, diagnose, and recover from errors:** Error messages should be expressed in plain language (no error codes), precisely describe the problem, and constructively suggest a solution. - **Help and documentation:** Any help or documentation should be easy to find, focused on the user’s task, and list the concrete steps to solve it. It also shouldn’t be too long. As mentioned at the beginning, both methods fall under the term expert evaluation. Used correctly, the method can uncover many problems and give you a good starting point for identifying the biggest weaknesses of a website or an application. But this is exactly where the biggest challenge of expert evaluation lies: using it correctly. Expert evaluation is often seen as a replacement for actual user testing instead of being used as a complementary tool. Expert evaluation can uncover many problems, but it has the drawback that some problems go undetected, while others get flagged that don’t actually exist. ## How Do You Use Expert Evaluation Correctly? Expert evaluation is excellent for forming usability hypotheses and for uncovering both major and minor problems. However, expert evaluation is NOT(!) a replacement for usability tests with real users, because usability experts can’t adequately represent the target audience. With that limitation in mind, let’s look at the following points for using the method correctly: 1. Use both the cognitive walkthrough and heuristic evaluation. Each method has its own pros and cons. If you use both, you can offset them to some extent. 2. Ideally, the usability experts shouldn’t have had any prior contact with the system. Under no circumstances should a usability expert evaluate a system they were involved in themselves. Even if the expert works to the best of their knowledge and conscience, they’ll subconsciously overlook errors. 3. Use several experts to evaluate the system – 3 to 5 experts is perfectly fine. But they have to run the test independently of the other testers to prevent groupthink and its downsides (fear of social rejection/desire for social approval). Only in the follow-up debrief do the experts pool their results. 4. The expert should be familiar with the system’s domain and also have solid knowledge of usability, user experience, and HCI (human-computer interaction). ## **Conclusion** Expert evaluation is far from perfect. But there are many situations in which it makes sense to use it. Without much effort, you can surface both major and minor issues and get an overview of problem areas. Afterward, further usability tests can be run based on these results to verify or disprove the findings from the expert evaluation.