Article

Publication Bias in Meta-Analysis: Its Meaning and Analysis

Author

황성동

Information

pp. 1~19 / 2016 Vol.23 No.1

Abstract

As a new mode of research synthesis, meta-analysis has recently drawn much attention from researchers,having proved to produce less biased results than the traditional research synthesis method. However,scholars may be suspicious about the results of meta-analysis due to publication bias as it occurs whenpublished studies represent a biased selection of the evidence. This study was designed to discuss themeaning of publication bias and conduct publication bias analysis using an example data set so as toprovide researchers with a guideline for performing valid meta-analysis. The process of publication biasanalysis begins with a careful examination of the effect sizes of individual studies and continues withtesting funnel plot asymmetry. With both a graphical test and a statistical one, potential publication biascould not be ruled out. To deal with this bias, adjustments were made using the trim-and-fill methodfollowed by the Copas selection model, and the original result was found to be valid and statisticallyrobust even with the small bias detected. In the academic circle of meta-analysis, publication bias analysisis specified as one of the required items in some guidelines of reporting and evaluating the results ofmeta-analysis. Therefore, it is highly recommended to conduct publication bias analysis for the validity ofmeta-analysis as well as the integrity of individual meta-analytic studies.

Keywords

References

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