Usability of Natural User Interfaces for People with Intellectual Disabilities

In today’s society, information and communication technologies are ubiquitous. They have become an essential part of people’s daily lives and have the potential to improve various areas of life and daily tasks of their users. However, these technologies are usually developed for the masses rather than for specific user groups, which makes their use difficult for a large part of the population, especially for people with intellectual disabilities. A possible improvement can be achieved by adapting the user interface to the abilities of the users. This work follows up on a previous study that evaluated current interface types and their adaptability. In this study, we evaluate the usability in the daily use of different technical solutions with a questionnaire using the System Usability Scale. Our questionnaire was completed by 31 participants with varying degrees of disability for 44 solutions. The results suggest that the usability of natural user interfaces is highly dependent on factors such as age, level of customization, or the type of solution used. We found that pointing gesture interfaces are currently the most commonly used type of interfaces. These were mainly used as a standalone input modality, but usability was perceived to be higher with additional system accessibility features. Interfaces with buttons or switches required more adaptation, and interfaces with voice interaction may have potential, but currently there are too many barriers to be usable for this target group.