Identifying and Prioritizing Age-Friendly Design Principles and Guidelines for Developing Transportation Planning E-Tools: A Scoping Review (Preprint)

BACKGROUND Older adults often face mobility challenges and usability barriers when navigating transportation options due to age-related physical, cognitive, and sensory changes. While transportation-planning e-tools can support their independence, most are not designed for their specific needs. There is a lack of comprehensive, age-friendly usability design principles tailored to this context. OBJECTIVE This study aims to identify, synthetize, and prioritize the most relevant age-friendly usability design principles and guidelines for developing transportation planning e-tools that are tailored to the needs of older adults. METHODS A scoping review was conducted following Arksey and O’Malley’s methodological framework, enhanced by guidance from the Joanna Briggs Institute and reported according to PRISMA-ScR standards. The literature search was performed across six following scientific databases: MEDLINE (PubMed, NCBI), AgeLine (EBSCOhost), Cochrane Library (Wiley Online Library), SCOPUS (Elsevier), IEEE Xplore (IEEE Xplore Digital Library), and TRID (Transportation Research Board), and supplemented by gray literature identified through Google Scholar and Google Search, covering the period from January 2013 to April 2025. To guide the analysis, four foundational usability frameworks, by Nielsen, Shneiderman and Plaisant, Gerhardt-Powals, and Weinschenk and Barker, were used to inductively derive generic principles that structured the classification of age-friendly guidelines. This process resulted in the organization of extracted guidelines into ten core usability principles. The Analytic Hierarchy Process (AHP) was used to rank the principles based on expert pairwise comparisons and their frequency of reference in literature. RESULTS The study identified 31 relevant studies. From these, 500 age-friendly guidelines were refined into 68 actionable guidelines across ten (10) usability principles: Visual Clarity, Structure & Navigation, Ease of Use, Information, Minimizing Memory Load, Feedback, Accessibility, Consistency, Simplicity, and Control. AHP ranked Visual Clarity (36.4%), Structure & Navigation (22.1%), and Ease of Use (12.5%) as the top three age-friendly design priorities. CONCLUSIONS This study offers an evidence-based foundation for developing transportation-planning e-tools that promote older adults’ autonomy and digital inclusion, with prioritized guidelines applicable to transportation-planning e-tools and to the broader field of age-friendly digital design. Ongoing updates and active user involvement are essential to ensure their sustained usability and long-term relevance.