title: The two-stage model of carcinogenesis: overcoming the nonidentifiability dilemma.
abstract: The two-stage mathematical model of carcinogenesis has been shown to be nonidentifiable whenever tumor incidence data alone is used to fit the model (Hanin and Yakovlev, 1996). This lack of identifiability implies that more than one parameter vector satisfies the optimization criteria for parameter estimation, e.g., maximum likelihood estimation. A question of greater concern to persons using the two-stage model of carcinogenesis is under what conditions can identifiable parameters be obtained from the observed experimental data. We outline how to obtain identifiable parameters for the two-stage model.
authors.affiliation: National Institute of Environmental Health Sciences, Laboratory of Computational Biology and Risk Assessment, Research Triangle Park, North Carolina 27709, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Sherman
authors.forename: C J
authors.initials: CJ
authors.lastname: Portier
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic; D003043:Cocarcinogenesis; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced; D008433:Mathematics; D008752:Methylene Chloride / Q000633:toxicity; D051379:Mice; D008954:Models, Biological; D012306:Risk
chemical_list: D008752:Methylene Chloride