title: Epidemiologic inquiry: observational studies.
abstract: A major objective of epidemiologic investigation is to determine whether or not an association between an exposure and a condition exists in a human population. The presence of such an association cna be explored using three distinct strategies, the cohort, the case-control, and the cross-sectional approaches. This paper describes each of these research designs and discusses their advantages and disadvantages.
authors.affiliation: Department of Family and Community Medicine, University of Missouri-Columbia 65201.
authors.forename: S C
authors.initials: SC
authors.lastname: Zweig
authors.forename: R L
authors.initials: RL
authors.lastname: Blake
mesh_terms: D004812:Epidemiologic Methods; D006801:Humans; D012307:Risk Factors