In recent years, many research activities have focused on design that aims to produce universally accessible systems, taking into account special needs of various user groups. These special needs are associated with many user factors, such as impairments of speech, hearing or vision, cognitive limitations, aging, as well as with various environmental factors. Fields that address this problem, such as Usability, Universal Accessibility, Universal Design, or Inclusive Design have been developed as relatively independent domains, but they share many aspects with other human-computer interaction (HCI) disciplines. However, researchers and practitioners are often not aware of interconnections among concepts of universal accessibility and "ordinary" HCI. In view of this situation, in this article we show there is a fundamental connection between multimodal interface design and universal accessibility, and that awareness of these links can help both disciplines. Researchers from these areas may use different terminology, but the concepts they use often have essentially the same meaning. We propose a unified conceptual framework where these areas can be joined.
Communications of the ACM
Human-Centered Data Analytics

Obrenovic, Z., Abascal, J., & Starcevic, D. (2007). Universal Accessibility as a Multimodal Design Issue. Communications of the ACM, 24(5), 83–88.