Effect of the “PAL” word prediction system on the quality and quantity of text generation

In the main, the value of rate-enhancement techniques in prostheses for people with severe speech disorders has been judged on the basis of simple measures such as rate of composition and keysaving. Comparative studies have not been conducted into long-term effects of the use of such systems. In addition the quality of the users' output can be as important as the quantity and the ease with which it can be produced. In this paper, long-term case studies of adults and children are discussed. Results show that a predictive word processing system can make valuable improvements to the quantity and quality of the written work of users with both physical impairments and spelling problems. In addition, some evidence has been found of the potential of orthographic predictive systems for assisting those with language disorders. It is argued that, in many clinical and educational situations, these effects can be more important than those indicated by simple measurements of rate enhancement and keysaving for such systems.