Methodology

Development of a wearable global positioning system for place and health research

Daniel Rainham¹ , Daniel Krewski¹ , Ian McDowell² , Mike Sawada³ and Brian Liekens⁴

¹McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Ontario, Canada

²Department of Epidemiology and Community Medicine, University of Ottawa, Ontario, Canada

³Department of Geography, Laboratory for Applied Geomatics and GIS Science (LAGGISS), University of Ottawa, Ottawa, Canada

⁴Department of Civil Engineering, Dalhousie University, Halifax, Canada

author email corresponding author email

International Journal of Health Geographics 2008, 7:59doi:10.1186/1476-072X-7-59

Published:	25 November 2008

Abstract

Background

An increasing number of studies suggest that characteristics of context, or the attributes of the places within which we live, work and socialize, are associated with variations in health-related behaviours and outcomes. The challenge for health research is to ensure that these places are accurately represented spatially, and to identify those aspects of context that are related to variations in health and amenable to modification. This study focuses on the design of a wearable global positioning system (GPS) data logger for the purpose of objectively measuring the temporal and spatial features of human activities. Person-specific GPS data provides a useful source of information to operationalize the concept of place.

Results

We designed and tested a lightweight, wearable GPS receiver, capable of logging location information for up to 70 hours continuously before recharging. The device is accurate to within 7 m in typical urban environments and performs well across a range of static and dynamic conditions.

Discussion

Rather than rely on static areal units as proxies for places, wearable GPS devices can be used to derive a more complete picture of the different places that influence an individual's wellbeing. The measures are objective and are less subject to biases associated with recall of location or misclassification of contextual attributes. This is important for two reasons. First, it brings a dynamic perspective to place and health research. The influence of place on health is dynamic in that certain places are more or less relevant to wellbeing as determined by the length of time in any location and by the frequency of activity in the location. Second, GPS data can be used to assess whether the characteristics of places at specific times are useful to explaining variations in health and wellbeing.