A Spatial Knowledge Acquisition Comparison Between Digital Visual Thematic Maps, Non-Visual Interactive Text Thematic Maps, and Tables

Original Abstract

Digital maps are used to communicate generalized spatial information and relationships, yet are commonly made "accessible" using tables that lack geographic information. This study examines whether these tables and interactive text maps (ITMs) may be comparable to visual maps. Twenty sighted and 20 blind and low-vision individuals (BLVIs) performed tasks designed to compare visual maps, ITMs, and tables. Participants answered numeric, geographic, and combined numeric geographic questions using each representation, and performance, preference, and NASA-TLX were measured. Across both participant groups, map representations (visual and ITMs) significantly outperformed tables on geographic-based questions, while performance differences were minimal for numeric questions. For sighted participants, performance on geographic questions did not significantly differ between visual maps and ITMs, indicating that a larger powered study may find an "equivalent purpose" across these two conditions. Participants preferred map-based representations over tables. Perceived workload was highest for the ITM, intermediate for the visual map, and lowest for the table. Consistent with the Map Equivalent Purpose Framework, these findings indicate that Web Content Accessibility Guidelines-compliant ITMs can provide access to spatial information, unlike tables. These findings challenge prevailing accessibility practice that recommends tables lacking geographic information as map alternatives, and motivate reconsideration of accessibility legislation exempting digital thematic maps.