Article info
PDFDigest
Digest
Citation
Digest
Publication history
- Accepted December 8, 2010
- First published January 4, 2011.
Online issue publication
April 18, 2016
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© 2011, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.