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. 2010 Aug 24;7(8):e1000329. doi: 10.1371/journal.pmed.1000329

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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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(A) October 2004–April 2008 (screen through 3, 6, and 12-mo follow-up): randomized intervention and attention-control groups. (B) December 2006–September 2007 (screen through 3-mo follow-up): nonrandomized standard control group.