Toward a qualitative epidemiology.

This article is based on an invited keynote lecture to the Qualitative Health Research meetings in Banff, Alberta, in April 2002 and so is written in an informal style. The author begins with problems in traditional epidemiology, with its focus on the case record and the epidemiological triad of host, agent, and environment. The idea of a person-in-context "movie" is offered as an alternative kind of case record, and broader issues of identity and context are added to enrich the explanations of those records. In the original presentation, an agent-based model in the style of complexity theory was demonstrated. That model is beyond the scope of this article and is now under review by a complexity journal; a draft manuscript is available on request.