Hanyang Med Rev.  2015 Feb;35(1):9-17. 10.7599/hmr.2015.35.1.9.

An Introduction of the Systematic Review and Meta-Analysis

• Shin WJ

• KMID: 2149099
• DOI: http://doi.org/10.7599/hmr.2015.35.1.9

Abstract

Systematic reviews and meta-analysis represent a specific type of medical research in which an original article is a unit of analysis. These methods of research are essential tools in integrating scientific information, increasing the internal and external validity of the conclusions of original articles, and suggesting areas for future research. Meta-analysis is becoming popular because it can combine results from similar studies to calculate an overall estimate of a treatment effect. They are also necessary for the practice of evidence-based medicine and the medical decision making. However, conducting good quality systematic reviews is not easy and difficult to interpret. Since analysis of a data with meta-analysis is a relatively new field of research, many clinicians have not had the opportunity to learn about systematic review and meta-analysis systematically. An introduction of the rationale for carrying out meta-analysis will be helpful to the clinician in interpreting the results of meta-analysis.

Keyword

Evidence-Based Medicine; Meta-Analysis; Review

MeSH Terms

Decision Making
Evidence-Based Medicine
Meta-Analysis as Topic

Figure

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  Fig. 1 Fixed-effect model; distribution of random error.

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  Fig. 2 Random-effect model; between study and within study variance.

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  Fig. 3 Example of a fixed-effect analysis.

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  Fig. 4 Example of a random-effect analysis.

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  Fig. 5 Example of a funnel-plot of precision by log odds ratio.

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