Notebook input devices put to the age test: the usability of trackpoint and touchpad for middle-aged adults

Abstract

In two experiments, the usability of input devices integrated into computer notebooks was under study. The most common input devices, touchpad (experiment 1) and trackpoint (experiment 2) were examined. So far, the evaluation of mobile input devices has been restricted to younger users. However, due to ongoing demographic change, the main target group of mobile devices will be older users. Therefore, the present study focused on ageing effects. A total of 14 middle-aged (40–65 years) and 20 younger (20–32 years) users were compared regarding speed and accuracy of cursor control in a point-click and a point-drag-drop task. Moreover, the effects of training were addressed by examining the performance increase over time. In total, 640 trials per task and input device were executed. The results show that ageing is a central factor to be considered in input device design. Middle-aged users were significantly slower than younger users when executing the different tasks. Over time, a significant training effect was observed for both devices and both age groups, although the benefit of training was greater for the middle-aged group. Generally, the touchpad performance was higher than the trackpoint performance in both age groups, but the age-related performance decrements were less distinct when using the touchpad.

Keywords:

• Ageing: Input device
• Computer notebook
• Touchpad
• Trackpoint
• Motor performance
• Cursor control
• Point-click task
• Point-drag-drop task

Acknowledgements

The authors extend their gratitude to all participants taking part in the experiment, especially the middle-aged users for their efforts and patience to execute so many click and drag-drop trials for the sake of research. Moreover, thanks to Philipp Brauner, who developed the software tool for the measurements of cursor movements and Sarah Hatfield for research support. Finally, thanks to Rob Stammers and two anonymous reviewers for critical comments on an earlier version of this manuscript.