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. 2011 Mar 8;6(3):e17684. doi: 10.1371/journal.pone.0017684

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Luo et al.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

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Of the 616 articles pulled for the UK, 18.8% (116) were international-corresponding (Intl-C), 34.4% (212) were international-secondary (Intl-S), 46.8% (288) were independent (Indep).