A statistical method of combining the results of a number of different studies
in order to provide a larger sample size for evaluation and to produce a
stronger conclusion than can be provided by any single study.
Source: GreenFacts
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Meta-analyses are attempted when previous studies were too small individually
to achieve meaningful or statistically significant results. Because combining
data from disparate groups is problematic, meta-analyses usually are considered
more suggestive than definitive.
