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Review
. 2022 Sep 30;37(5):e428.
doi: 10.5001/omj.2022.42. eCollection 2022 Sep.

Introduction to Systematic Reviews and Meta-analyses of Therapeutic Studies

Murtadha Al-Khabori  1 , Wasif Rasool  2
Affiliations
Review

Introduction to Systematic Reviews and Meta-analyses of Therapeutic Studies

Murtadha Al-Khabori et al. Oman Med J. .

Abstract

A systematic review is a specific and reproducible method to search, identify, select, appraise, and summarize all studies relevant to a particular health care question. In this paper, we will review the concept of level of evidence, define the terms systematic review and meta-analysis, and outline the steps in performing a systematic review and meta-analysis with an illustrative example. We will also introduce some important concepts in systematic reviews and meta-analyses like heterogeneity, publication bias, forest plots, and quality assessment. Finally, this review will focus on systematic reviews addressing therapeutic research questions.

Keywords: Clinical Trial; Meta-Analysis; Systematic Review.

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Figures

Figure 1
Figure 1
Forest plot with random-effects model.
Figure 2
Figure 2
Forest plot with fixed-effects model.
Figure 3
Figure 3
Funnel plot with no asymmetry.
Figure 4
Figure 4
Funnel plot with asymmetry.
See this image and copyright information in PMC

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