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5029254 
Book/Book Chapter 
Chapter 22: Power statistics for meta-analysis : tests for mean effects and homogeneity 
Lajeunesse, MJ 
2013 
Princeton University Press 
Princeton, NJ 
Handbook of Meta-analysis in Ecology and Evolution 
English 
is part of a larger document 5029185 Handbook of Meta-analysis in Ecology and Evolution
The common justification for meta-analysis is the increased statistical power to detect effects over what is obtained from individual studies. For ecologists and evolutionary biologists, the statistical power of meta-analysis is important because effect sizes are usually relatively small in these fields, and experimental sample sizes are often limited for logistic reasons. Consequently, many studies lack sufficient power to detect an experimental effect should it exist. This chapter provides a brief overview of the factors that determine the statistical power of meta-analysis. It presents statistics for calculating the power of pooled effect sizes to evaluate nonzero effects and the power of within- and between-study homogeneity tests. It also surveys ways to improve the statistical power of meta-analysis, and ends with a discussion on the overall utility of power statistics for meta-analysis.