Primer on Systematic Review and Meta-Analysis

  • Marcello TonelliEmail author
  • Dan Hackam
  • Amit X. Garg
Part of the Methods in Molecular Biology™ book series (MIMB, volume 473)


A systematic review uses an explicitly defined process to comprehensively identify all studies pertaining to a specific focused question, appraise the methods of the studies, summarize the results, identify reasons for different findings across studies, and cite limitations of current knowledge. Meta-analyses usually combine aggregate-level data reported in each primary study, which may provide a more precise estimate of the “true effect” than any individual study. However, the conclusions may be limited by between-trial heterogeneity, publication bias, or deficits in the conduct or reporting of individual primary studies.


Systematic review meta-analysis randomized controlled trials study heterogeneity publication bias 


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.University of AlbertaEdmonton, AlbertaCanada
  2. 2.Division of Clinical Pharmacology and ToxicologyUniversity of TorontoTorontoCanada
  3. 3.Department of MedicineUniversity of Western OntarioLondonCanada

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