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Reevaluating Heterogeneity in Evidence Synthesis
Published online by Cambridge University Press: 23 September 2025
Abstract
Evidence synthesis has recently seen an enormous increase across many different scientific disciplines. Despite its popularity, it has also been the subject of significant criticism. One of the main critiques of evidence synthesis is the existence and treatment of heterogeneity between primary studies. The aim of this article is to reexamine heterogeneity in evidence synthesis, including perspectives from evolutionary biology, ecology, and conservation. I argue that while some of the critiques of heterogeneity remain valid, there are contexts where it is much less problematic. Furthermore, I propose that heterogeneity can be useful because analyzing it can provide valuable information.
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