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A simple formula for sample size calculation in equivalence studies.

Paul Zhang
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Abstract

Bioequivalence and clinical equivalence can be claimed based on the two one-sided test approach or the confidence interval approach. Consequently the power function of the equivalence test can be derived from either noncentral t-distribution or central t-distribution. The sample size is then determined from the power function either by numerical method or closed formulas. In this paper, we propose a simple formula for sample size calculation based on central t-distribution. The proposed formula has better properties than those currently available and it can be easily applied in all equivalence studies.

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Confidence IntervalsDrug EvaluationMathematical ComputingModels, StatisticalSample SizeTherapeutic EquivalencyJournal Article

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Paul Zhang. 2003. A simple formula for sample size calculation in equivalence studies.. https://doi.org/10.1081/bip-120022772

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