One of the most productive methods available to geographic epidemiology is the comprehensive health survey of isolated villages. Most epidemiologic research has concentrated on the depth analysis of particular hypotheses relating to specific disease problems. By contrast, in the comprehensive health-survey approach the focus is on total ecology. The epidemiologic unit is the village. It is a fallacy, however, to think that a village is a simple organism even though ecologic characteristics seem fairly clear. The long history of traditional and static living permit remarkably complex social adaptations to local ecosystems. Village variations provide a whole series of natural experiments that permit comparative analysis.
This type of research requires investigators with unique characteristics. They must be truly ecologic in their thinking. They must be able to apply sophisticated technologic methods. Present comprehensive health surveys in isolated areas are possible largely because of improved equipment.