Integrating GIS into the Study of Contextual Factors Affecting Injection Drug Use Along the Mexico/US Border

Abstract

While the relationship between individual-level factors and drug use or associated risk behaviors has been investigated in-depth, comparatively little is known about the influence of contextual determinants. Geographic information systems (GIS) enable users to simultaneously display a number of environmental data layers and use spatial statistics to explore the relationships between contextual and individual-level variables. This makes GIS a potentially powerful tool in substance use research. One area where geography has a striking influence on health is at the US/Mexico border, where the confluence of drug trafficking routes, migration, and income inequalities form unique environmental influences on drug use scenes. In this chapter, we describe some of the spatial and environmental issues, such as migration, neighborhood characteristics, and proximity to services, which may affect drug use behaviors and risks. A number of practical methods to measure geographical indicators are also described, focusing on a case study of injection drug use in the Mexico/US border city of Tijuana, Mexico.