An estimating equation approach for the analysis of case-control studies with exposure measured at several levels

Liang gave an extension of the Mantel-Haenszel estimating procedure for a common odds ratio to logistic regression models. It is applicable to case-control studies with multiple exposure levels, which yield K 2 x J tables. This paper provides variance and covariance estimators, which are consistent in both sparse-data and large-strata, for Liang's estimating functions in the K 2 x J tables case, and proposes an approximate confidence interval method for the common odds ratios.