Effectiveness of hand- and foot-operated secondary input devices for word-processing tasks before and after training

Previous research has shown that, without practice, users are slower using the foot than the hand to control input devices. This study compared the performance (before and after practice) of users operating a foot-controlled secondary input device (foot mouse) with the performance of users operating a hand-controlled secondary input device (hand trackball) to complete four word-processing tasks requiring various amounts of keyboard and secondary input device use. Before practice, hand trackball performance was better on all tasks. After practice, hand trackball performance was better on all tasks except the task requiring the greatest amount of keyboard use, for which there was no significant difference between devices. For all tasks, practice improved performance with the foot mouse but not with the hand trackball. These findings suggest that, with enough practice, it may be efficient for users to use a foot input device for tasks that also require keyboard input.