Susan L. Norris, MD, MPH; David Atkins, MD, MPH
Randomized, controlled trials (RCTs) are firmly established as the standard for determining which medical treatments are effective. In some areas of health care, however, among them surgery, public health, and the organization of health care delivery, most evidence addressing the effectiveness of clinical or policy interventions rests on nonrandomized studies. We examine the use of study designs other than RCTs in Evidence-based Practice Center reports addressing questions of the effectiveness of treatment interventions. These reports offer the opportunity to examine the approaches used and the challenges faced by reviewers when nonrandomized studies are included and their quality assessed. We then offer recommendations for using these studies in systematic reviews of treatment interventions.
RCT = randomized, controlled trial.
Included are reports that examined 1 or more questions of clinical effectiveness ( = 49). Bars represent the number of reports that included the specific study design. Totals exceed 49 because each report can include more than 1 clinical question and more than 1 study design.
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Norris SL, Atkins D. Challenges in Using Nonrandomized Studies in Systematic Reviews of Treatment Interventions. Ann Intern Med. 2005;142:1112–1119. doi: 10.7326/0003-4819-142-12_Part_2-200506211-00011
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Published: Ann Intern Med. 2005;142(12_Part_2):1112-1119.
Cardiac Diagnosis and Imaging, Cardiology, Coronary Risk Factors, Diabetes, Endocrine and Metabolism.
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Print ISSN: 0003-4819 | Online ISSN: 1539-3704
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