Bachelor’s thesis

The aim of this thesis was to study how a list of design system specific cognitive accessibility heuristic principles could be developed. Additionally, the study aimed to observe how well this list of principles would work as a tool for the heuristic evaluation of a design system’s cognitive accessibility.

The theoretical section of this thesis focuses on the background, principles and key terms of heuristic evaluation, cognitive accessibility, and design systems. Additionally, the thesis discusses key principles of user interface and user experience design and the design process of services.

The study was conducted in accordance with the Grounded Theory method. Heuristic principles for usability, a list of principles for improving cognitive accessibility and a guide for the usage of design systems were used as research material in the study. The evaluation of the functionality of the list of principles developed during this process was carried out using a case example. During this case example a website was evaluated with the list of principles.

The results of the case study showed that the list of heuristic principles was well suited for situations where the goal of the evaluation was to quickly map the overall picture of the cognitive accessibility of a product or service. However, an element or component-specific list should be used in addition to this list if a more detailed picture of the state of cognitive accessibility is needed. The list of principles proved useful as an evaluation tool. However, the list should be iterated on in the future to take matters like the ways in which design systems work better into consideration.