Keyboard and mouse errors due to motor disabilities

There are many people who find the standard computer input devices-the keyboard and mouse-difficult to use due to a motor disability. A number of keyboard and mouse configuration options designed to overcome physical difficulties exist. However, formal empirical evaluation of such facilities is rare. There is, in fact, little data available on the precise nature of physical difficulties with input devices. Hence, it is difficult to gauge the adequacy of existing access provision. This paper presents an empirical study of the. keyboard and mouse errors encountered in a sample of 20 computer users with motor disabilities, and six without disabilities. Six important classes of keyboard difficulty are identified, involving significant correction time for participants with disabilities. Difficulties with all aspects of mouse usage were observed, particularly pointing and dragging. Many of the difficulties observed would be amenable to automatic detection. It is hoped that these results will help to inform the development of more accessible software and hardware.