Explaining variations in obesity and inactivity between US metropolitan areas.

This paper discusses measurement of the main dimensions of the urban environment that have been proposed as relevant to explaining geographic variations in obesity and inactivity. It considers urban sprawl, food access and exercise access as latent constructs, defined by sets of observed indicators for areas. In an application to 993 US metropolitan counties, the paper shows how these latent constructs may be incorporated in an ecological (area-scale) model, which recognizes spatial aspects in the patterning of both outcomes and environmental factors. Urban sprawl and area socioeconomic status emerge from regression modelling as leading influences on obesity and inactivity. [ABSTRACT FROM AUTHOR]