The relationship between chi-square statistics from matched and unmatched analyses.
The McNemar chi-square statistic for testing the equality of proportions in matched pairs of binary data is expressed as a function of the Pearson chi-square statistic and a kappa statistic for measuring interrater agreement. Implications for data analysis and for sample size determination are discussed. The result is generalized to provide a similar relationship between Cochran's Q-statistic and the Pearson chi-square statistic for the comparison of proportions in matches of size m.
Department of Epidemiology and Biostatistics, University of Western Ontario, London, Canada.
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Donner
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Li
D016009:Chi-Square Distribution; D006801:Humans