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Controlling of confounders is one of the most important methodological issues in epidemiological studies because the associations of exposures and outcomes are very much influenced by confounders. Matching, stratification and multivariate statistical methods are frequently used to control the effects of confounders. This paper introduces two statistical package programs: Mantel-Haenszel method for stratification and logistic regression analysis for multivariate analysis. For explanation of the package programs, data on the association of body mass index with adenomatous polyp of colon in the United States was used.