Dr Jane Littlehales

Littlehales, J.M. Multimodal user interfaces: an investigation and evaluation. Birmingham: School of Computer Science, University of Birmingham, 1995.

Multimodal user interfaces are no easier to use than single mode interfaces despite the many claims made about them by their designers. Single mode interfaces, such as command language, natural language and direct manipulation, do have disadvantages but combining two or more of them into a multimodal interface does not eliminate the disadvantages. This has been shown by analysing features of multimodal interfaces, investigating other systems and designing and building an interface which has then been evaluated. The evaluation testing took the form of user trials, comprising the multimodal interface with a single mode interface (natural language) to the same system. The results showed that, while multimodal output was preferred by users and found to be beneficial, multimodal input gave rise to more errors and was stated to be more difficult to use than the single mode input.