Exploratory Study of Administrators’ Perceptions and Usability Evaluation Practices in Open Data Visualization Systems

The effectiveness of open data visualization systems depends on their usability and accessibility, two attributes that are rarely examined in depth. This study examined how the administrators of 12 such systems in Colombia perceive and evaluate both, and how their reported practices compare with independently assessed accessibility characteristics. A mixed-methods design combined an administrator survey, a heuristic walkthrough, and automated audits with the AEL Accessibility Checker (ACC), Google Lighthouse, EqualWeb, and TAW. Half of the administrators (6/12) reported that the usability of their system had been evaluated; none of those six reported evaluating more often than every six months, and two reported test-based methods. Five of the six reported evaluating accessibility. TAW reported between 11 and 685 violations per audited page and EqualWeb between 9 and 202 (these tool-specific counts are not directly comparable). All five institutions that reported evaluating accessibility had tool-reported violations on their audited pages. Dedicated accessibility controls, which WCAG does not require at level AA, were observed in one system, belonging to an institution that reported no evaluation. This pattern tentatively suggests that accessibility is treated more as a compliance matter than as a core design requirement. Low-cost, accessibility-focused evaluation routines are proposed for consideration; their effectiveness was not tested, and studies with end users are needed.