Newman S C
Department of Psychiatry, University of Alberta, Edmonton, Canada.
J Clin Epidemiol. 1988;41(1):59-65. doi: 10.1016/0895-4356(88)90009-1.
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.
一个三状态马尔可夫过程被用于对稳态人群进行建模。推导了经典的P = ID方程，以及一些最初由米耶蒂宁（《美国流行病学杂志》1976年；103: 226 - 235）和弗里曼与哈钦森（《美国流行病学杂志》1980年；112: 707 - 723。同刊1986年；124: 134 - 149）报道的恒等式。使用理论和实证方法证明，在稳态人群中进行的患病率 - 患病率病例对照研究得出的优势比通常将是发病密度比的有偏估计。然而，除非发病密度比至少为10或更高，否则该偏差可能不具有实际重要性。
