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September 2009

In this month's Editorial the PLoS Medicine Editors discuss the importance of valid negative results, and their immediate and open availability, in maintaining the integrity of the medical literature, especially when clinical effectiveness is at issue. The Editorial suggests that physicians mindful of Hippocrates's vow "first do no harm" should appreciate that a study "that questions the accepted or desired way of doing things can be at least as important as one that supports a new approach." Given the US movement to undertake comparative effectiveness research (CER)—which calls for a wide range of study designs to "assist consumers, clinicians and policy-makers in making informed decisions"—the Editorial argues for transparency in the design and reporting of all types of research, including data that cast doubt on prevailing practices.

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