If someone has problems using a standard keyboard there are various alternatives that may be easier for them to use. Devices that can be plugged directly into the USB or keyboard socket on the computer are the easiest to set up and should be able to work with all standard software.
Before discounting the standard keyboard make sure that the difficulties are not caused by a poor working position. Also ensure that the problems noted are not due to other factors such as a learning difficulty or visual problems.
Remember that some common keyboarding problems can be resolved by changing the accessibility settings in your computer's control panel.
Miniature keyboards and compact keyboards require less effort and reach. This can be useful for someone with a muscular weakness. People with uncoordinated movements can also find that they have better control of their movements over a smaller distance. Keyboards with built in pointing devices can help people whose reach is limited.
Expanded keyboards such as the Jumbo Board or Big Keys LX have larger keys that can be more easily targeted. Ergonomic keyboards, which include built in wrist-rests, have been developed to help reduce the risk of RSI.
Maltron produce a range of keyboards to speed up input for people with limited hand function.
• The Use of Overlay Keyboards
• IntelliKeys Classic
• IntelliKeys US
More info on Physical Disabilities