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Practical guide to sample size calculations: superiority trials
Laura Flight1, Steven A Julious1
1Medical Statistics Group, University of Sheffield, Sheffield, UK.
Abstract:
A sample size justification is a vital part of any investigation. However, estimating the number of participants required to give meaningful results is not always straightforward. A number of components are required to facilitate a suitable sample size calculation. In this paper, the steps for conducting sample size calculations for superiority trials are summarised. Practical advice and examples are provided illustrating how to carry out the calculations by hand and using the app SampSize.
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