Use of recurrence plots to characterize search strategies of elderly population on web-based telemedicine systems

An Internet-based telemedicine has emerged as an effective tool for providing healthcare and health-related information, especially in rural areas which often have a larger elderly population. However, the interfaces of currently existing internet-based telemedicine systems were not specifically developed for elderly users. This research investigated the characteristics of older adult visual behavior during health related web-page information searches using recurrence plots (RP) as a new tool for this use. RP is a two-dimensional representation of data used to measure time constancy for nonlinear data dynamics that are instantly apparent whether a system is periodic or chaotic. Overall, across seven given tasks, the older adults used sequential search strategies even though their rates and the duration of searches varied. Most of the older adults tended to use horizontal or vertical search strategies except in those cases where they were quickly able to find the target by systematically moving their gazes from left to right, right to left, top to bottom, or bottom to top to navigate on the menu areas. Amongst the three major menu areas, the main menu was fixated on most often followed by the right vertical menu area. Unlike the younger adult subjects, the older adults frequently utilized the right vertical menu as well as the main menu. RPs successfully presented the visually characterized search scanning sequences and quantified apparent visual patterns by using arrays of dots in an N x N square in time order.