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Critical Care
Published in: Critical Care 4/2002

01-08-2002 | Review

Statistics review 4: Sample size calculations

Authors: Elise Whitley, Jonathan Ball

Published in: Critical Care | Issue 4/2002

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Abstract

The present review introduces the notion of statistical power and the hazard of under-powered studies. The problem of how to calculate an ideal sample size is also discussed within the context of factors that affect power, and specific methods for the calculation of sample size are presented for two common scenarios, along with extensions to the simplest case.
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Metadata
Title
Statistics review 4: Sample size calculations
Authors
Elise Whitley
Jonathan Ball
Publication date
01-08-2002
Publisher
BioMed Central
Published in
Critical Care / Issue 4/2002
Electronic ISSN: 1364-8535
DOI
https://doi.org/10.1186/cc1521

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