Pairwise comparisons in the analysis of carcinogenicity data

Mohammad A. Rahman, Ram C. Tiwari

Division of Biometrics-6, Office of Biostatistics, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, USA.
Office of Biostatistics, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, USA.

DOI: 10.4236/health.2012.410139                

Abstract

Analysis of carcinogenicity data generally involves a trend test across all dose groups and a pairwise comparison of the high dose group with the control. The most commonly used test for a positive trend is the Cochran-Armitage test. This test is asymptotically normal. For the pairwise comparison of the high dose group with the control group, we propose two modifications: the first modification is to apply the test on the data from high dose and control groups after dropping the data from the low and the medium dose groups; the second modification is to adjust the test conditional on data from all dose groups. We compare the power performance of these two modifications for the pairwise comparisons.

Keywords

Carcinogenicity Study; Trend Test; Pairwise Test; Exact Test

Conflicts of Interest

The authors declare no conflicts of interest.

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