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Introduction to Meta-Analysis

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Principles and Practice of Clinical Trials

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Abstract

Studies within a systematic review are often combined statistically in a meta-analysis, which quantitatively synthesizes all available evidence about the relative effects of two healthcare interventions for the same clinical outcome. A key issue in every meta-analysis is whether the identified randomized control trials (RCTs) are similar enough to be combined together since important differences in trial- or patient-level characteristics may affect the treatment effects. Such differences, called heterogeneity, need to be properly investigated and accounted for in the analysis. In this chapter, we introduce the basic concepts of meta-analyses of RCTs and we describe the two main meta-analytical models, namely, the common effect and the random effects models. Then, we present several ways to identify and assess heterogeneity. We discuss the interpretation of results from a meta-analysis using two exemplar datasets. The chapter closes with a brief introduction to more sophisticated meta-analytical techniques such as the use of individual participant data and network meta-analysis.

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Author information

Authors and Affiliations

  1. Université de Paris, Research Center of Epidemiology and Statistics (CRESS-U1153), INSERM, Paris, France

    Theodoros Evrenoglou, Silvia Metelli & Anna Chaimani

  2. Assistance Publique - Hôpitaux de Paris (APHP), Paris, France

    Silvia Metelli

  3. Cochrane France, Paris, France

    Anna Chaimani

Authors
  1. Theodoros Evrenoglou
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  2. Silvia Metelli
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  3. Anna Chaimani
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Corresponding author

Correspondence to Anna Chaimani .

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. Department of Epidemiology, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, United States

    Tianjing Li

  2. The Johns Hopkins Center for Clinical Trials and Evidence Synthesis, Johns Hopkins University, Baltimore, MD, USA

    Curtis L. Meinert

  3. Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA

    Steven Piantadosi

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Evrenoglou, T., Metelli, S., Chaimani, A. (2021). Introduction to Meta-Analysis. In: Piantadosi, S., Meinert, C.L. (eds) Principles and Practice of Clinical Trials. Springer, Cham. https://doi.org/10.1007/978-3-319-52677-5_287-1

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  • DOI: https://doi.org/10.1007/978-3-319-52677-5_287-1

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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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