Mobility is vital to healthy aging. The built environment is central to mobility as it is the setting where mobility occurs. Older adults of low socioeconomic status (SES) may be especially reliant on built environments that support non-motorized mobility. Despite this, older adults of low SES are underrepresented in research.

Therefore, this dissertation applies quantitative methods to describe the mobility (capacity and enacted function) and investigate the association between the built environment and nonmotorized mobility (walking for transportation and physical activity) of older adults of low income. The studies within this dissertation are set in Metro Vancouver;​ the last three utilize data from a cross-sectional study of 161 older adults of low income.

The first study investigates the reliability of a novel approach (virtual audits) for measuring the built environment. I found that virtual audits reliably measure macroscale (neighbourhood-level) built environment features that promote older adult walking, but may be inappropriate for measuring fine-grain details of the microscale (street-level) built environment.

The second study provides an in-depth description of the mobility of older adults living on low income. I noted that participants generally had the capacity to be mobile and made a high proportion of walking trips, although these did not together serve to meet physical activity guidelines for most.

The third study analyzes travel diary data to identify destinations that older adults most commonly visit in a week (i.e., grocery stores, malls, restaurants/cafes);​ I also found that each 10-point increase in Street Smart Walk Score (measure of the built environment) was associated with a 20% increase in walking for transportation (IRR = 1.20, 95% CI = 1.12, 1.29).

The fourth study analyzes accelerometry and self-report data to investigate associations between the built environment and physical activity and walking for transportation. Odds of any walking for transportation were 1.45 (95% CI = 1.18, 1.78) times greater for each 10-point increase in Street Smart Walk Score. There were no other built environment-mobility associations.

Taken collectively, these studies fill methodological gaps in the literature and provide data on an understudied population that may be especially reliant on built environments that support walking.