title: Odds ratio estimation in a steady-state population.
abstract: A three-state Markov process is used to model a steady-state population. The classical P = ID equation is derived, as well as a number of identities originally reported by Miettinen (Am J Epidemiol 1976; 103: 226-235) and Freeman and Hutchison (Am J Epidemiol 1980; 112: 707-723. Ibid. 1986; 124: 134-149). Using theoretical and empirical methods it is demonstrated that the odds ratio derived from a prevalence-prevalence case-control study conducted in a steady-state population will generally be a biased estimate of the incidence density ratio. However the bias will not likely be of practical importance unless the incidence density ratio is at least 10 or more.
authors.affiliation: Department of Psychiatry, University of Alberta, Edmonton, Canada.
authors.forename: S C
authors.initials: SC
authors.lastname: Newman
mesh_terms: D000206:Actuarial Analysis; D000367:Age Factors; D003627:Data Interpretation, Statistical; D004812:Epidemiologic Methods; D006801:Humans; D008962:Models, Theoretical; D011336:Probability