title: Links between categories of interaction.
authors.affiliation: Biometry Branch, National Cancer Institute, Bethesda, MD 20892-4200.
authors.forename: D L
authors.initials: DL
authors.lastname: Weed
authors.forename: M
authors.initials: M
authors.lastname: Selmon
authors.forename: T
authors.initials: T
authors.lastname: Sinks
mesh_terms: D004812:Epidemiologic Methods; D004813:Epidemiology; D004992:Ethics, Medical; D008962:Models, Theoretical