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Chapter 12 - Sample Size Calculations

Published online by Cambridge University Press:  20 April 2023

Jos W. R. Twisk
Jos W. R. Twisk
Affiliation:
Amsterdam University Medical Centers
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Summary

In Chapter 12 sample size calculations for longitudinal studies are discussed. It is shown that a sample size calculation for longitudinal studies is based on the standard sample size calculation formula with an additional multiplication factor which includes the number of follow-up measurements and the estimated correlation between the repeated measurements. Sample size calculations for both a continuous and a dichotomous outcome variable are illustrated with an example. Besides the practical part of the sample size calculation, the chapter also includes a discussion regarding the sense or nonsense of sample size calculations.

Keywords

standard sample size calculationmultiplication factorcontinuous outcome variabledichotomous outcome variablesense or nonsense of sample size calculations
Type
Chapter
Information
Applied Longitudinal Data Analysis for Medical Science
A Practical Guide
 , pp. 216 - 219
Publisher: Cambridge University Press
Print publication year: 2023

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  • Sample Size Calculations
  • Jos W. R. Twisk, Amsterdam University Medical Centers
  • Book: Applied Longitudinal Data Analysis for Medical Science
  • Online publication: 20 April 2023
  • Chapter DOI: https://doi.org/10.1017/9781009288002.013
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  • Sample Size Calculations
  • Jos W. R. Twisk, Amsterdam University Medical Centers
  • Book: Applied Longitudinal Data Analysis for Medical Science
  • Online publication: 20 April 2023
  • Chapter DOI: https://doi.org/10.1017/9781009288002.013
Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

  • Sample Size Calculations
  • Jos W. R. Twisk, Amsterdam University Medical Centers
  • Book: Applied Longitudinal Data Analysis for Medical Science
  • Online publication: 20 April 2023
  • Chapter DOI: https://doi.org/10.1017/9781009288002.013
Available formats
×