Comparing three head-pointing systems using a single subject design.

The keyboard is the most commonly used input method for interfacing with computers. When using a keyboard is not possible, alternative computer input methods are needed. Three methods using head control are: Head Master by Prentke Romich, Free Wheel by Pointer Systems, and LROP by Words+. The purpose of this study was to compare these three methods for speed and accuracy using a single subject design for nine individuals with disabilities. Visual inspection of the data revealed that subjects obtained higher scores when using Head Master and LROP than Free Wheel. As a follow-up test, an analysis of variance test for repeated measures showed no difference between using Head Master and LROP but did show a significant difference between Head Master and Free Wheel, and LROP and Free Wheel.