How do you know if a finding in social science is, well, real?

Students of science are taught not to take the results of a single study as the absolute truth. The rule of thumb is to seek out systematic reviews, or meta-analyses, which pull together lots of studies looking at the same question and weigh their rigor to come to a more fully supported conclusion.

But can we trust all this meta-science? Not necessarily. Positive, confirmatory findingsoften make their way into the published literature, while negative findings collect dust in file drawers. This means meta-analyses, too, can be biased.

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