Analysing the travel behaviour of older adults: what are the determinants of sustainable mobility?

In recent years, various authorities launched projects that aim to make their cities more age-friendly. Designing age-friendly cities is a complex and context-dependent process that requires clear implementation guidelines for policy makers. As one of the eight domains of age-friendly cities, transportation is a critical component of making our cities more liveable for older adults and their families. This paper contributes to the literature by exploring the travel behaviour of older adults with a focus on the factors that lead to sustainable mobility patterns. Our empirical analysis is based on survey data collected from 1,221 older adults as part of the Age-Friendly Columbus project in Columbus, Ohio in the United States of America. We develop multinomial logistic regression models to investigate the travel mode choices of older adults (auto only, non-auto options only and multimodal (auto and at least one non-auto option)). We include age and built environment characteristics as the key variables, with lifestyle-related factors and socio-demographics as controls in our analysis. We find older respondents were more likely to use autos only compared to younger respondents. Our analysis also reveals significant associations between built environment characteristics and travel mode choices. Interaction effects show that the relationships between built environment characteristics and travel preferences differed by age cohorts among older individuals. The primary contribution of this study is that it provides evidence on what built environmental improvements help to promote sustainable travel among older adults in mid-sized and auto-dependent metropolitan cities. We argue that these improvements contribute to older adults' sustainable mobility, as well as out-of-home activity behaviour, social engagement and individual health. The results of this study may especially benefit non-driver older adults who lack reliable non-auto alternatives for their daily travel.