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. 2008 Jan 3;5(1):e4.
doi: 10.1371/journal.pmed.0050004.

In the era of systematic reviews, does the size of an individual trial still matter

Gordon H Guyatt  1 , Edward J Mills, Diana Elbourne
Affiliations

In the era of systematic reviews, does the size of an individual trial still matter

Gordon H Guyatt et al. PLoS Med. .

Abstract

Systematic reviews that combine high-quality evidence from several trials are now widely considered to be at the top of the hierarchy of clinical evidence. Given the primacy of systematic reviews-and the fact that individual clinical trials rarely provide definitive answers to a clinical research question-some commentators question whether the sample size calculation for an individual trial still matters. Others point out that small trials can still be potentially misleading.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

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