OUR TOOLS / EXPERTISE

Because our goal is to produce better science, we invest quite a lot of energy in the development of new tools that can help us better understand our world. Here are some of our achievements...



GPS and accelerometer sensor devices

A Multisensor device for health monitoring

Our team has developed a wearable multisensor device for continuous tracking of location, physical activity, and other physiological measures, with over-the-air transmission capacities. The device, called SenseDoc, integrates a GPS, a tri-axial accelerometer, a GPRS for data transmission through cell-phone network, and an ANT+ chip for further wireless connections of additional sensors. It has a strong battery life (3 days without recharge with 1-s epoch GPS data and up to 100Hz accelerometry) and can send data over-the-air in real-time, which opens great possibilities for prompted recall or monitoring of device usage, mobility and outcomes. The ANT protocol allows further addition of complementary sensors including footpods, heart rate monitors, or continuous glucometers. Finally, RFID tags can be used to track indoor movements or social contacts. The device is currently used in several studies in Canada and France. Contact us for additional information.

​Activity place detection algorithm for GPS data 

Global Positioning System trackers are increasingly used in health research to get a better sense of daily mobility and related exposures. Yet, GPS data can get messy. That's why we developed a novel kernel-based algorithm to easily derive activity places and trips from raw GPS data. You can download and use this algorithm in ArcToolBox format for ArcGIS here. All the details are provided in a paper in International Journal of Health Geographics. The toolbox also contains a procedure to generate artificial GPS tracks. 

Although some may see the use of artificial tracks instead of real-life tracks as a limitation - we believe this is a great tool to evaluate and compare the performance of your algorithm. When using real-life GPS data, certain track characteristics - such as noise or stop points - are not always known precisely. This makes it difficult to test algorithms, and to know what eventually makes them less efficient. With artificial GPS tracks, you have total control on the amount of GPS noise, stop locations and stop durations. This allows to test your algorithm under a wide range of known conditions. See our paper in IJHG about this procedure and our novel kernel based algorithm. 



Activity space questionnaires

VERITAS Questionnaire

Together with the RECORD Group from INSERM (France) with whom we have a long history of collaboration, we developed a novel interactive map-based questionnaire called VERITAS (Visualisation, Evaluation and Recording of Itineraries and Activity Spaces). This questionnaire allows to easily collect detailed spatial information, using a map. To know more, see this paper published in AJPM and contact us for use or adaptation of VERITAS to your study.

ISIS Activity Space

Questionnaire

We developed a self-complete activity space questionnaire to be used in the Interdisciplinary Study on Inequalities in Smoking. Respondents are asked to provide detailed geographic information on the location where they study, work, shop for groceries, practice sports/physical activity, conduct leisure activities and two other, unspecified activities. The questionnaire can be completed online, over the phone or on paper. It has been tested for convergent validity and results were published here. A pdf. version of the questionnaire can also be accessed here: French or English. Contact us for questions or comments!



Spatial and Land use and Datasets

​MEGAPHONE GIS

At SPHERELAB, we have a comprehensive Geographic Information System that contains a vast array of spatial information on the social and built environments. This GIS, along with highly skilled expertise in geomatics and spatial analysis among team members, allows to characterise environments for various health research projects. Contact us for more information.