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Basics of meta-analysis

  • POSTGRADUATE CORNER: RESEARCH TECHNIQUES
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Abstract

Meta-analysis is an approach to formally, systematically and quantitatively analyze multiple existing research studies and to synthesize new research findings based upon the existing data. Until the late 1970s, meta-analyses were not regularly reported in the medical literature, but since then there has been an exponential growth of meta-analyses and they are now among the most frequently cited form of research. A properly performed systematic review and meta-analysis is a very important tool in evidence-based medicine and a good understanding of the steps involved in doing a systematic review and meta-analysis is important to yield meaningful results. The purpose of this review article is to provide a brief overview about systematic reviews and meta-analyses and the underlying principles for conducting this type of research. Methodological approaches for conducting a meticulous meta-analysis are described and the important steps involved in the interpretation and presentation of meta-analysis are outlined and discussed. The key objective of this paper is to outline a step-by-step approach that is useful to all researchers, who would like to conduct their first meta-analysis. This paper also provides clinicians and researchers with the information to interpret systematic reviews and meta-analyses.

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Author information

Authors and Affiliations

  1. Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane, QLD, Australia

    Ayesha Shah & Gerald J. Holtmann

  2. Translational Research Institute Queensland, Woolloongabba, QLD, Australia

    Ayesha Shah & Gerald J. Holtmann

  3. Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia

    Ayesha Shah & Gerald J. Holtmann

  4. Department of Psychology, Macquarie University, Sydney, NSW, Australia

    Michael P. Jones

Authors
  1. Ayesha Shah
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  2. Michael P. Jones
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  3. Gerald J. Holtmann
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Contributions

Ayesha Shah and Gerald J Holtmann - review idea, concept and design, drafting of the manuscript and review of final manuscript. Mike P Jones - drafting of the manuscript, review of final manuscript.

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Correspondence to Gerald J. Holtmann.

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AS, MPJ, and GJH declare that they have no conflict of interest.

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The authors are solely responsible for the data and the contents of the paper. In no way, the Honorary Editor-in-Chief, Editorial Board Members, the Indian Society of Gastroenterology, or the printer/publishers are responsible for the results/findings and content of this article.

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Shah, A., Jones, M.P. & Holtmann, G.J. Basics of meta-analysis. Indian J Gastroenterol 39, 503–513 (2020). https://doi.org/10.1007/s12664-020-01107-x

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