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PubMed · 3663825

A simple approximation for calculating sample sizes for detecting linear trend in proportions.

J M Nam
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Abstract

A simple approximate formula for sample sizes for detecting a linear trend in proportions is derived. The formulas for both the uncorrected and corrected Cochran-Armitage test are given. For two binomial proportions these reduce to those given by Casagrande, Pike, and Smith (1978, Biometrics 34, 483-486). Some numerical results of a power study for small sample sizes show that the nominal power corresponding to the approximate sample size is a reasonably good approximation to the actual power.

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BibTeXRIS

J M Nam. 1987. A simple approximation for calculating sample sizes for detecting linear trend in proportions.. https://pubmed.ncbi.nlm.nih.gov/3663825/

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