Teach or design? How older adults' use of ticket vending machines could be more effective

The dominance of computer technology in work and leisure poses challenges for older people. Their lack of computer experience and computer literacy impedes their ability to explore and use new interactive systems. This is particularly challenging for the design of public access systems, such as ticket vending machines (TVM). This article describes a conflict relevant for many designers considering age-related differences in technology use: should the user be taught to use the existing design or should the design be changed to accommodate older users? An experiment was conducted to directly compare these alternative approaches with each other and with a simulation of an existing TVM. It compares three TVM designs regarding the usability criteria of effectiveness, efficiency and satisfaction, controlling for age, and cognitive and motivational characteristics. 62 older (M = 68 years) and 62 younger (M = 25 years) participants were split into three groups: The control group solved 11 tasks using a simulation of the TVM, the video group watched a brief instructional video before solving the same tasks with the same TVM, and the wizard group used a redesigned wizard interface instead. Results indicate that young and old participants' performance improved after watching the video, but older participants improved more, reaching the effectiveness of the young control group. In the wizard condition, age differences in effectiveness and satisfaction were eliminated; however, speed differences remained in all conditions. The results suggest that the simple integration of minimal video instruction or a task-oriented wizard design can make public access systems truly universally usable, and that the wizard TVM was a true "walk-up-and-use system."