meta-analysis

n. technique or procedure of synthesizing the results of a research by combining the results of a number of independent studies

In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. The first meta-analysis was performed by Karl Pearson in 1904, in an attempt to overcome the problem of reduced statistical power in studies with small sample sizes; analyzing the results from a group of studies can allow more accurate data analysis.
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A method for statistically combining the findings of independent studies (usually published studies and usually many) into a group of conclusions.