Abstract Marginal structural Cox Models (Cox MSMs) have been used to estimate the causal effect of a time-varying treatment on the hazard when there exist time-dependent confounders, which are themselves also affected by previous treatment. A Cox MSM can be estimated via the...

Abstract The bivariate kernel density-ratio estimator has developed popularity among epidemiologists as a flexible exploratory tool for examining the spatial variation in the risk of disease. This estimator is simply given as the quotient of a “case” density estimate describing the observed...

Abstract Purpose: The nested case–control study design, in which a fixed number of controls are matched to each case, is often used to analyze exposure–response associations within a cohort. It has become common practice to sample four or five controls per case; however, previous research has...

Abstract The problem of misclassification is common in epidemiological and clinical research. In some cases, misclassification may be incurred when measuring both exposure and outcome variables. It is well known that validity of analytic results (e.g. point and confidence interval estimates for...

Abstract Matched pairs appear frequently in studies of the association between a dichotomous exposure and a dichotomous outcome. The standard conditional logistic regression estimator of the common odds ratio is consistent, but uses only information from the doubly discordant pairs. To gain...

Abstract Capture recapture methods using data on cases appearing on overlapping incomplete lists have been widely used for prevalence estimates. Nevertheless, workers have, in general, employed several different methods and there appears no consensus as to which is optimal.The authors, using...

Abstract The paper considers the properties of and relations between confounding and effect modification from the perspective of causal inference and with a distinction drawn as to how each of these two epidemiologic concepts can be defined both with respect to a distribution of potential...