title: Bias reduction in conditional logistic regression.
abstract: We employ a general bias preventive approach developed by Firth (Biometrika 1993; 80:27-38) to reduce the bias of an estimator of the log-odds ratio parameter in a matched case-control study by solving a modified score equation. We also propose a method to calculate the standard error of the resultant estimator. A closed-form expression for the estimator of the log-odds ratio parameter is derived in the case of a dichotomous exposure variable. Finite sample properties of the estimator are investigated via a simulation study. Finally, we apply the method to analyze a matched case-control data from a low birthweight study.
authors.affiliation: Department of Statistics, Texas A& M University, College Station, TX 77843, U.S.A.
authors.forename: Jenny X
authors.initials: JX
authors.lastname: Sun
authors.forename: Samiran
authors.initials: S
authors.lastname: Sinha
authors.forename: Suojin
authors.initials: S
authors.lastname: Wang
authors.forename: Tapabrata
authors.initials: T
authors.lastname: Maiti
mesh_terms: D015982:Bias; D016022:Case-Control Studies; D003198:Computer Simulation / Q000706:statistics & numerical data; D015987:Effect Modifier, Epidemiologic; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D016015:Logistic Models