. 2010 Dec 1;11:95. doi: 10.1186/1471-2296-11-95
Copyright ©2010 Levesque et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (<url>http://creativecommons.org/licenses/by/2.0</url>), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 2.
Study design.