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Cluster Randomized Trials

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Book cover Principles and Practice of Clinical Trials

Abstract

In a randomized clinical or field trial, when randomization units are comprised of groups of individuals, many aspects of design and analysis differ greatly from those of an individually randomized trial. In this chapter, we highlight those features which differ the most, explaining the nature of the differences and delineating approaches to accommodate them. The focus is on design, as many readers will be familiar with the correlated data analysis techniques that are appropriate for many (although not all) cluster randomized trials (CRTs). Thus, the chapter begins by covering motivations for using a CRT design, basic correlation parameters, the variety of potential estimands, delineation and randomization of clusters, and sample size calculation. This is followed by sections on the analysis and reporting of results, which highlight ways to handle the multilevel nature of the data. Finally, ethical and monitoring considerations unique to CRTs are discussed.

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Author information

Authors and Affiliations

  1. Departments of International Health and Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA

    Lawrence H. Moulton

  2. Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK

    Richard J. Hayes

Authors
  1. Lawrence H. Moulton
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  2. Richard J. Hayes
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Corresponding author

Correspondence to Lawrence H. Moulton .

Editor information

Editors and Affiliations

  1. Samuel Oschin Comprehensive Cancer Insti, WEST HOLLYWOOD, CA, USA

    Steven Piantadosi

  2. Bloomberg School of Public Health, Johns Hopkins Center for Clinical Trials Bloomberg School of Public Health, Baltimore, MD, USA

    Curtis L. Meinert

Section Editor information

  1. Statistician, MRC Clinical Trials Unit at UCL, Institute of Clinical Trials and Methodology, London, UK

    Babak Choodari-Oskooei

  2. MRC Clinical Trials Unit and Institute of Clinical Trials and Methodology, University College of London, London, England

    Mahesh Parmar

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Moulton, L.H., Hayes, R.J. (2020). Cluster Randomized Trials. In: Piantadosi, S., Meinert, C. (eds) Principles and Practice of Clinical Trials. Springer, Cham. https://doi.org/10.1007/978-3-319-52677-5_108-1

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  • DOI: https://doi.org/10.1007/978-3-319-52677-5_108-1

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-319-52677-5

  • Online ISBN: 978-3-319-52677-5

  • eBook Packages: Springer Reference MathematicsReference Module Computer Science and Engineering

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