Although methodologists have long recognized that randomized trials provide stronger evidence than nonrandomized observational studies, for management decisions in which randomized trials are unavailable, clinicians and guideline developers must still rely on observational studies. Indeed, for a great many questions of clinical importance, observational studies constitute the best available evidence. In these situations, clinicians, guideline developers, and decision makers rightly expect guidance from methodologists in the use and interpretation of those studies and their integration into guideline recommendations.
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Published online: January 07, 2008
Accepted: May 21, 2007
© 2008 Elsevier Inc. Published by Elsevier Inc. All rights reserved.