Abstract
Systematic reviews can help practitioners keep abreast of the medical literature by summarizing large bodies of evidence and helping to explain differences among studies on the same question.A systematic review involves the application of scientific strategies, in ways that limit bias, to the assembly, critical appraisal, and synthesis of all relevant studies that address a specific clinical question. A meta-analysis is a type of systematic review that uses statistical methods to combine and summarize the results of several primary studies. Because the review process itself (like any other type of research) is subject to bias, a useful review requires clear reporting of information obtained using rigorous methods. Used increasingly to inform medical decision making, plan future research agendas, and establish clinical policy, systematic reviews may strengthen the link between best research evidence and optimal health care.
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Author, Article, and Disclosure Information
Authors:
Deborah J. Cook,
From McMaster University, Hamilton, Ontario, Canada; and University of Texas Health Science Center and Veterans Affairs Hospital, San Antonio, Texas.
Acknowledgments: We would like to acknowledge many persons for their advice and support, particularly the following.
Grant Support: Dr. Cook is a Career Scientist of the Ontario Ministry of Health; Dr. Mulrow is Senior Research Associate at the Audie L. Murphy Memorial Veterans Hospital; and Dr. Haynes is a National Health Scientist of the National Health Research and Development Program of Health Canada.
Corresponding Author: Deborah J. Cook, MD, MSc, Department of Medicine, St. Joseph's Hospital, 50 Charlton Avenue East, Hamilton, Ontario L8N 4A6, Canada.
Current Author Addresses: Dr. Cook: Department of Medicine, St. Joseph's Hospital, 50 Charlton Avenue East, Hamilton, Ontario L8N 4A6, Canada.
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