%0 Journal Article %T Using GPS technology to (re)-examine operational definitions of ¡®neighbourhood¡¯ in place-based health research %A Bryan J Boruff %A Andrea Nathan %A Sandra Nij£¿nstein %J International Journal of Health Geographics %D 2012 %I BioMed Central %R 10.1186/1476-072x-11-22 %X Informed by Global Positioning Systems (GPS) tracking data, several alternative neighbourhood delineation techniques were examined (i.e., variable width, convex hull and standard deviation buffers). Compared with traditionally used buffers (i.e., circular and polygon network), differences were found in built environment characteristics within the newly created ¡®neighbourhoods¡¯. Model fit statistics indicated that exposure measures derived from alternative buffering techniques provided a better fit when examining the relationship between land-use and walking for transport or leisure.This research identifies how changes in the spatial extent from which built environment measures are derived may influence walking behaviour. Buffer size and orientation influences the relationship between built environment measures and walking for leisure in older adults. The use of GPS data proved suitable for re-examining operational definitions of neighbourhood. %K Built environment %K Physical activity %K Neighbourhood effects %K Older adults %K GPS %K GIS %U http://www.ij-healthgeographics.com/content/11/1/22/abstract