SUNY Buffalo Study Uses Smartphones to Collect Time-Activity Data for Long-Term Personal-Level Air Pollution Exposure Assessment

Published December 3, 2014

While many people consider their smartphones to be lifesavers because they help organize and consolidate daily activities, Mark L. Glasgow is exploring ways to use smartphones to literally help save lives.

A study that Glasgow and colleagues from the University at Buffalo’s School of Public Health and Health Professions (SPHHP) have published in the November edition of the Journal of Exposure Science and Environmental Epidemiology, uses smartphones to collect time-activity data for long-term personal-level air pollution exposure assessment.

Because of the variability of people and air pollutants within cities, the researchers knew it was important to account for a person’s movements over time when estimating personal air pollution exposure. This study aimed to examine the feasibility of using smartphones to collect personal-level time-activity data using Skyhook Wireless’s hybrid geolocation module.  Through this module, the researchers developed an Android smartphone application called “Apolux” (Air, Pollution, Exposure), designed to track participants’ location in five-minute intervals for three months.  From 42 participants, the study compared Apolux data with contemporaneous data from two self-reported, 24-hour time-activity diaries.

About three-fourths of measurements were collected within five minutes of each other, and 79 percent of participants reporting constantly powered-on smartphones had a daily average data collection frequency of less than 10 minutes. Apolux’s degree of temporal resolution varied across manufacturers, mobile networks, and the time of day that data collection occurred. The discrepancy between diary points and corresponding Apolux data was 342.3 m (Euclidian distance) and varied across mobile networks. The study’s high compliance and feasibility for data collection demonstrated the potential for integrating smartphone-based time-activity data into long-term and large-scale air pollution exposure studies.

Glasgow, a MS student in epidemiology, and associate professor Lina Mu, PhD, in the Departmen of Epidemiology and Environmental Health at the University at Buffalo School of Public Health and Health Professions, were lead authors of the study.  SPHHP co-authors of the study included fellow department of epidemiology and environmental health students Joel Merriman and Christina Crabtree-Ide; as well as Department of Epidemiology and Environmental Health faculty members Carole B. Rudra, PhD, and Jean Wactawski-Wende, PhD.  The study was funded by a two-year grant from the National Institutes of Health.