Examining commute routes : applications of GIS and GPS technology

Objective: The application of geographic information systems (GIS) to describe commute route elements is commonplace, yet the accuracy of GIS-estimated commute routes is not clear. This study compared GIS-estimated commute routes against actual routes traveled as measured using global positioning systems (GPS) to examine differences in urban form surrounding travel routes across different buffer sizes and travel modes. Methods: Thirty-seven adults from Auckland, New Zealand participated in the study between January and March 2008. Participants wore GPS units and completed a travel log for 7 days. GPS data were integrated into a GIS database to ascertain commute routes. Results: Overall, 29 commute journeys were appropriately captured by GPS. Levels of agreement between actual and shortest commute routes were dependent on the buffer size selected, built environment variable examined, and travel mode. Conclusions: Despite technical difficulties, GPS assessment of routes traveled is recommended to provide an accurate assessment of commute journey urban form elements.