title: Elucidation of some epidemiologic principles.
abstract: This review is an attempt to elucidate some fundamental epidemiologic concepts, particularly various aspects of the case-referent design and its relations to the cohort type of study. Some of these aspects also have direct implications for judgements about the comparability of differently exposed population groups, eg, with regard to confounding.
mesh_terms: D004812:Epidemiologic Methods; D006801:Humans; D009017:Morbidity; D012107:Research Design; D012306:Risk