ABSTRACT
Spatial epidemiology is the description and analysis of geographical data, specifically health data, in the form of counts of mortality or morbidity, and factors that may explain variations in those counts over space. Advances in spatio-temporal methodology that address the challenges of modeling with increasingly complex data have been driven in part by increased awareness of the potential effects of environmental hazards and potential increases in the hazards themselves. This chapter starts by describing the underlying concepts behind investigations into the effects of environmental hazards and, in particular, the importance of considering diseases and exposures over both space and time in epidemiological analyzes. Actual exposures to an environmental hazard depend on the temporal trajectories of the population's members that will take individual members of that population through a sequence of micro-environments, such as a car, house or street.
