Methodology for evaluating the user interface quality of the tax portal

Since the beginning of the 21st century, in correlation with the fourth industrial revolution, humanity has been surrounded by advanced digital technologies that are changing everyday life on planet Earth and beyond. People are aware of the necessity of constant progress, innovation, and complex digital transformation at the level of the state, companies and society. The environmental, economic and social upheavals of recent years and months show us that the technological world is a fundamental element of our survival. During the outbreak of the COVID-19 pandemic or the war in Ukraine, it became essential to increase the level of digitalization of the public sector to effectively inform the general public. The coexistence of electronic governments and citizens predetermines the success of solving future crises and should therefore be given sufficient attention. The effective functioning of the state depends on public sector revenues from taxes and fees, the collection of which is in many ways facilitated and improved by appropriately configured digital and communication technologies. The user-friendly design of web applications plays a pivotal role in increasing the motivation and active participation of users, which e-governments do not always manage to achieve. The dissertation addresses the topic of the user interface design of an e-government tax portal in order to develop a methodology for evaluating its quality. The main objective is to create a set of recommended applicable practices and procedures for evaluating the design of the user interface of the tax portal. To achieve the goal, the theoretical framework of the thesis integrates the theoretical thematic area of the concept of e-government and the digitalization process into the context of user interface design. The content analysis of three European tax portals provides data for comparison and synthesis and the subsequent creation of a methodology for evaluating the quality of the graphical user interface of the state tax portal. Illustrative testing example indicates the possible way of methodology application, and its relevance and usability are verified by the results of interviews with six experts. The methodology, adapted for feasible usage by public administration workers, summarizes the main design and user experience principles relevant to the tax portal website into five groups of evaluation indicators divided into 19 categories and 72 indicators. Experts evaluate the methodology as comprehensible and usable, with a recommendation for further development with additional metrics to increase the level of usability. The results of the work reveal new findings and insights for the knowledge enrichment of the general public, for use by state administrations, for discussion across the political spectrum and decision-making bodies, and for the inspiration and development of scientific fields (UX development, UI and web design, GUI development, visual interface design, information architecture, coding, content strategy for the web).