Abstract

Digital services, ranging from online shopping and banking to government services and healthcare, are rapidly taking over human-provided services. The accessibility and usability of such digital services may not allow older adults to make use of them, making automation a barrier to access societal services. This is especially critical with many healthcare-related services and apps. This research is framed around two interrelated constructs, task complexity and individual complexity, the latter influenced by cognitive decline in older users. The experiment has three representative tasks of different task complexity and the measure of individual complexity which is understood through previous knowledge of participants (eHealth literacy), from different age groups, 18-25 years old and over 65 years old. The dependent measure is usability, measured by task-related performance as well as subjective measures (SUS; Brooke et al., 1996, and NASA-TLX; Hart and Staveland, 1988). The results suggest that the Task Complexity Index (TCI) is a valid measure for usability. In addition, older adults seem to experience more usability issues than younger adults. However, the individual complexity measure of previous knowledge (eHealth literacy) does not seem to have a significant impact on usability.

Publication Date

5-5-2026

Document Type

Thesis

Student Type

Graduate

Degree Name

Experimental Psychology (MS)

Department, Program, or Center

Psychology, Department of

College

College of Liberal Arts

Advisor

Esa M. Rantanen

Advisor/Committee Member

Kristoffer Whitney

Advisor/Committee Member

Wendy Rogers

Campus

RIT – Main Campus

Download

Share

COinS