Pairwise comparisons in the analysis of carcinogenicity data


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.

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Rahman, M. and Tiwari, R. (2012) Pairwise comparisons in the analysis of carcinogenicity data. Health, 4, 910-918. doi: 10.4236/health.2012.410139.

Conflicts of Interest

The authors declare no conflicts of interest.


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