Considerations When Using Individual GPS Data in Food Environment Research: A Scoping Review of ‘Selective (Daily) Mobility Bias’ in GPS Exposure Studies and Its Relevance to the Retail Food Environment

Abstract

Advancements in geospatial technologies including geographic -information systems and global positioning system (GPS) devices have provided insights on how the retail food environment might be contributing to the ongoing obesity epidemic. Caution has been raised, however, around the potential for research that uses GPS-captured activity spaces to overestimate the impact that exposure to food retailers has on food choices and behaviour. This phenomenon, where it is difficult to discern whether an individual is passively exposed to a space or actively seeks it out, is referred to as a `selective (daily) mobility bias'. Researchers' understanding of this bias is relatively new and understudied, particularly in the food environment literature, where the bias could have serious implications. This chapter reviews 14 peer-reviewed papers and two doctoral theses to identify and critique the methods proposed for handling this bias and offer recommendations to consider as the use of GPS-activity space studies continues to grow.