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. 2009 Nov 13;4(11):e7747. doi: 10.1371/journal.pone.0007747

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Snellman 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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Each value is designated by a box. The height of the wide grey bars indicates mean values and the error bars display 95% confidence intervals for the means.