The Effect of Disability and Approach on Touch Screen Performance during a Number Entry Task

As touch screen technology improves in functionality and decreases in price, these input devices are becoming increasingly more integrated into daily life. People are frequently required to interact with touch screens at places ranging from their local grocery stores to airport check-in kiosks. Since it is becoming necessary for people to use touch screens in order to access needed products or services, we conducted an experiment to examine how individuals with varying motor control disabilities perform on a simple number entry task. Since some individuals may also be wheelchair users, and the Americans with Disabilities Act Accessibility Guidelines allows for the touch screen to be approachable by a wheelchair user from the front or parallel (side), the effect of approach on performance was also evaluated. Participants with and without motor control disabilities, including wheelchair users, performed a number entry task on a number pad with different combinations of button and gap sizes, while seated at a touch screen kiosk. Results revealed that participants with motor control impairments had significantly more inaccurate touches overall than participants without. Performance from the front orientation was significantly more accurate than from the side for all participants, regardless of the presence of a motor control disability. Results from this study may be used to guide design of touch screen accessibility for individuals with motor control disabilities and wheelchair users.