PRISM development: Iterative design using human factors tools

Purpose: We conducted a field trial to assess the relative benefits of: (i) a computer system referred to as PRISM (Personal Reminder Information and Social Management) versus (ii) a paper-based system containing comparable information (e.g., community information, educational resources, games). To evaluate the differential effects, we had to ensure that both systems were usable by and useful for the target users (i.e., older adults at risk for social isolation). In addition, the instructions for use and the training had to be clear and effective. To that end, we employed a human factors approach to the development of the PRISM system. Human factors practitioners investigate the capabilities and limitations of people and the demands placed on them when they interact with a system. Method: Our approach was multifaceted: (i) needs assessment with target users - we conducted a survey of older adults with computer experience to determine how they used a computer and the internet; (ii) we interviewed older adults who lack computer experience to assess their needs and interest in PRISM; (iii) we identified a prototype system to use as the starting point for PRISM and conducted a heuristic evaluation and cognitive walk-through by experts; (iv) we conducted detailed user testing of all experimental materials; and (v) we developed and tested a detailed instruction and support system. Results & Discussion: The survey and interviews yielded content ideas and challenges to be met in the design of the system. The evaluation by experts and target users identified user needs and design recommendations that were implemented in the redesign (e.g., meaningful icons and labels, navigation demands). The need for extensive training and instructional support became clear through the development and testing process, and thus these materials were integral to the implementation process. Overall, these data illustrate how human factors assessment tools provided valuable insights for design of the field trial, a necessary first step to ensure reliable and valid behavioral assessments.