Comparing children ’s GPS tracks with geospatial proxies for exposure to junk food

This study conducts a GIS-based analysis of GPS tracks—‘activity spaces’—and 21 proxies for activity spaces (e.g. buffers, container approaches) for a sample of 526 children (ages 9–14) in London, Ontario, Canada. These measures are combined with a validated food environment database (including fast food and convenience stores) to create a series of junk food exposure estimates and quantify the errors resulting from use of different proxy methods. Results indicate that exposure proxies consistently underestimate exposure to junk foods by as much as 68%. This underestimation is important to policy development because children are exposed to more junk food than estimated using typical methods.
Source: Spatial and Spatio-temporal Epidemiology - Category: Epidemiology Source Type: research