The term Usability Test refers to a series of methodologies which, through the study of real user behaviours, are designed to improve a website’s usability. During the usability testing, work is carried out on various fronts, beginning with the identification of any issues or bottle necks in the interface; it is therefore possible to make any necessary modifications to the design. It is essential to understand how a user thinks. Only then does it become possible to understand the real issues facing them and to be able to work towards resolving them during the planning phase.
The test format provides for the specific observation of each user’s behaviour individually, rather than as a group. Furthermore, it is essential that the assigned tasks are the same for every participant in the testing procedure. These features are common to all Usability Test techniques. There are some other specific characteristics which vary according to project specifications.
What is the experimental test?
Among Usability Test procedures, several methodologies can be identified. The experimental test is the strictest. It is extremely complex and begins with the identification of all the variables involved in the interaction of the individual user with the site. Once subjects have been selected according to a sample, an authentic scientific experiment is constructed, including the control of the variables involved and the attempt to disprove a specified hypothesis.
The experimental data obtained is then assessed. The relevant data is gathered in order to measure the variable which is being checked, in order to provide a statistical analysis. The experimental test method involves the use of groups numbering between 12 and 30 individuals.
The simplified test
Another methodological approach to the Usability Test is the simplified test. In this case, the main aim is to obtain indications relating to elements of the interface which obstruct the correct use of the site by an average user. It is a simplified version of the experimental method and a procedure which requires:
- The presence of an interface with partial functionality. Alternatively, some sketches of the website may be used;
- A full list of tasks assigned to the test participants;
- A quiet location with a similar connection to that used by the average user;
- A professional observer capable of putting the participants at ease without influencing their actions.
Testing sessions can be recorded, although the use of cameras is not recommended as it can make the users feel uncomfortable. Audio recording is however required when the so-called Thinking aloud technique is used, which involves the vocalisation of cognitive processes as they happen.
Which method should you choose?
In the world of the web, the first of these methodologies is very rarely used. The reason is related to its high costs and its focus on a very limited number of variables. The simplified test guarantees superior results, considering that it is able to focus on more creative aspects such as how people interact with website interfaces.
In order to obtain good results, it is fundamental not to consider (often involuntary) behaviours designed to please the experiment manager. As far as costs are concerned, it should be remembered that they vary according to a range of factors but they are still sustainable. The guaranteed benefits are very attractive, allowing specific issues to be identified, thereby avoiding problems dragging on until the website is launched online, resulting in potential damage which could in the end be much more expensive than a Usability Test procedure.
Translated by Joanne Beckwith