Usability testing is a technique used in user-centered interaction design to evaluate a product by testing it on users. This can be seen as an irreplaceable usability practice, since it gives direct input on how real users use the system. This is in contrast with usability inspection methods where experts use different methods to evaluate a user interface without involving users.
Usability testing focuses on measuring a human-made product’s capacity to meet its intended purpose. Examples of products that commonly benefit from usability testing are foods, consumer products, web sites or web applications, computer interfaces, documents, and devices. Usability testing measures the usability, or ease of use, of a specific object or set of objects, whereas general human–computer interaction studies attempt to formulate universal principles.
Simply gathering opinions on an object or document is market research or qualitative research rather than usability testing. Usability testing usually involves systematic observation under controlled conditions to determine how well people can use the product.However, often both qualitative and usability testing are used in combination, to better understand users’ motivations/perceptions, in addition to their actions.
Rather than showing users a rough draft and asking, “Do you understand this?”, usability testing involves watching people trying to use something for its intended purpose. For example, when testing instructions for assembling a toy, the test subjects should be given the instructions and a box of parts and, rather than being asked to comment on the parts and materials, they are asked to put the toy together. Instruction phrasing, illustration quality, and the toy’s design all affect the assembly process.Setting up a usability test involves carefully creating a scenario, or realistic situation, wherein the person performs a list of tasks using the product being tested while observers watch and take notes (dynamic verification). Several other test instruments such as scripted instructions, paper prototypes, and pre- and post-test questionnaires are also used to gather feedback on the product being tested (static verification). For example, to test the attachment function of an e-mail program, a scenario would describe a situation where a person needs to send an e-mail attachment, and ask him or her to undertake this task. The aim is to observe how people function in a realistic manner, so that developers can see problem areas, and what people like. Techniques popularly used to gather data during a usability test include think aloud protocol, co-discovery learning and eye tracking.
Hallway testing is a quick, cheap method of usability testing in which randomly-selected people—e.g., those passing by in the hallway—are asked to try using the product or service. This can help designers identify “brick walls”, problems so serious that users simply cannot advance, in the early stages of a new design. Anyone but project designers and engineers can be used (they tend to act as “expert reviewers” because they are too close to the project).
Remote usability testing
In a scenario where usability evaluators, developers and prospective users are located in different countries and time zones, conducting a traditional lab usability evaluation creates challenges both from the cost and logistical perspectives. These concerns led to research on remote usability evaluation, with the user and the evaluators separated over space and time. Remote testing, which facilitates evaluations being done in the context of the user’s other tasks and technology, can be either synchronous or asynchronous. The former involves real time one-on-one communication between the evaluator and the user, while the latter involves the evaluator and user working separately. Numerous tools are available to address the needs of both these approaches.
Synchronous usability testing methodologies involve video conferencing or employ remote application sharing tools such as WebEx. WebEx and GoToMeeting are the most commonly used technologies to conduct a synchronous remote usability test. However, synchronous remote testing may lack the immediacy and sense of “presence” desired to support a collaborative testing process. Moreover, managing inter-personal dynamics across cultural and linguistic barriers may require approaches sensitive to the cultures involved. Other disadvantages include having reduced control over the testing environment and the distractions and interruptions experienced by the participants’ in their native environment. One of the newer methods developed for conducting a synchronous remote usability test is by using virtual worlds.
Asynchronous methodologies include automatic collection of user’s click streams, user logs of critical incidents that occur while interacting with the application and subjective feedback on the interface by users.Similar to an in-lab study, an asynchronous remote usability test is task-based and the platform allows researchers to capture clicks and task times. Hence, for many large companies, this allows researchers to better understand visitors’ intents when visiting a website or mobile site. Additionally, this style of user testing also provides an opportunity to segment feedback by demographic, attitudinal and behavioral type. The tests are carried out in the user’s own environment (rather than labs) helping further simulate real-life scenario testing. This approach also provides a vehicle to easily solicit feedback from users in remote areas quickly and with lower organizational overheads. In recent years, conducting usability testing asynchronously has also become prevalent and allows testers to provide feedback in their free time and from the comfort of their own home.