CHANGE IN WEB ACCESSIBILITY OF MUNICIPAL WEBSITES (2024–2025) AND THE ROLE OF POPULATION SIZE: EVIDENCE FROM BULGARIA
Keywords:
web accessibility, municipal websites, WCAG compliance, public sector, digital inclusionAbstract
The purpose of this study is to assess the level, structure, and temporal dynamics of web accessibility in Bulgarian municipal websites, and to examine whether accessibility outcomes are associated with municipal size or demonstrate systematic improvement over time. The analysis is based on an almost complete national coverage of 264 out of 265 municipal websites, which allows the study to describe the actual structural state of accessibility rather than infer trends from a sample. Accessibility was evaluated in two consecutive years (2024 and 2025) using the automated WAVE assessment tool, with official population data incorporated as a proxy for municipal capacity. Given the highly skewed and zero-inflated nature of accessibility error distributions, non-parametric statistical methods were employed, including Wilcoxon signed-rank tests to assess temporal change and Spearman rank correlations to examine associations between municipality size and both accessibility levels and their dynamics. The results indicate no statistically significant improvement in overall web accessibility at the national level, even after controlling for extreme outliers, and no consistent relationship between municipality size and either the level or rate of change in accessibility. Although the number of websites with zero detected errors increased over time, this improvement was counterbalanced by stagnation or deterioration among a substantial proportion of municipalities, resulting in increased dispersion and institutional inequality. Domain-specific analyses show that the most prevalent and harmful accessibility barriers – particularly those related to contrast, navigation, and text alternatives – remain structurally stable and widespread, while observed changes are largely confined to technical domains such as ARIA and empty interactive elements and affect only a limited subset of websites. The study concludes that web accessibility in the municipal sector is characterized by institutional inertia and fragmentation, driven more by ad hoc technological updates than by coordinated governance or policy implementation, highlighting the need for stronger institutional accountability, systematic monitoring, and capacity-building to advance digital inclusion in the public sector.
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