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. 2006 Sep 29;1(5):e25. doi: 10.1371/journal.pctr.0010025

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This is an open-access article distributed under the terms of the Creative Commons Public Domain declaration which stipulates that, once placed in the public domain, this work may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose.

This is an open-access article distributed under the terms of the Creative Commons Public Domain declaration, which stipulates that, once placed in the public domain, this work may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose.

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*, including not undergoing the intervention at all; +, “net” risks are determined by the extent to which the risks exceed the potential for clinical benefit; #, some regulations allow RECs to approve greater than minimal risk interventions when the risk is no more than a minor increase over minimal and the study meets several other conditions.