Factors influencing time-location patterns and their impact on estimates of exposure: the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air)

We assessed time-location patterns and the role of individual- and residential-level characteristics on these patterns within the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air) cohort and also investigated the impact of individual-level time-location patterns on individual-level estimates of exposure to outdoor air pollution. Reported time-location patterns varied significantly by demographic factors such as age, gender, race/ethnicity, income, education, and employment status. On average Chinese participants reported spending significantly more time indoors and less time outdoors and in transit than white, black, or Hispanic participants. Using a tiered linear regression approach, we predicted time indoors at home and total time indoors. Our model, developed using forward selection procedures, explained 43 percent of the variability in time spent indoors at home, and incorporated demographic, health, lifestyle, and built environment factors. Time-weighted air pollution predictions calculated using recommended time indoors from USEPA(1) overestimated exposures as compared to predictions made with MESA Air participant-specific information. These data fill an important gap in the literature by describing the impact of individual and residential characteristics on time-location patterns and by demonstrating the impact of population-specific data on exposure estimates

Physical environments that promote physical activity among older people

Characteristics of neighbourhoods, streets, and public open spaces can hinder or facilitate physical activity (PA) among older adults. This chapter aims to critically review key conceptual and theoretical frameworks and the empirical evidence about the relationships between aspects of the physical environment and older adults’ PA. Access to local shops, services, public transport, public open spaces (e.g., parks), and recreational facilities within walking distance along well-maintained and aesthetically pleasing streets with high-quality pedestrian infrastructure appeared to be key determinants of PA among older adults. Therefore, policies underpinning the implementation of such environments should be evaluated to further strengthen the evidence base