How accessible are transport surveys? A scoping review of current practice and gaps

Online surveys have become a central tool in travel behaviour research, offering efficient and scalable ways to collect data. However, the extent to which these surveys are designed to be accessible for people with disabilities remains unclear. This paper addresses this gap through a narrative scoping review that examines how accessibility is considered and reported in transport studies that use online surveys. The review is guided by three questions: first, to what extent do transport studies report the use of accessibility measures; second, what types of adaptations are used to support participation among people with visual, cognitive, and learning disabilities; and third, what recommendations can be drawn from existing studies to guide more inclusive survey design in future transport research. The review of 38 studies published between 2019 and 2025 indicates limited reporting of accessibility considerations within survey practice. Only a small number of studies explicitly describe accessible recruitment approaches, survey adaptations, or compatibility with assistive technologies. Even in studies that include disabled participants, the reporting of accessibility measures is inconsistent or absent. These patterns suggest that accessible online survey design is not systematically integrated within transport research methodologies. To support the development of more inclusive practices, the paper synthesises the review findings into an accessibility evaluation metric comprising elements such as: overall accessibility adaptations, inclusive recruitment strategy, survey tool adaptations, pilot testing for accessibility, multiple access modes, assistive technology support, and accessibility modifications presented. The paper further provides a set of practical, evidence-based dimensions to guide more inclusive online data-collection practices, positioning accessibility as a core methodological requirement rather than an optional enhancement.