. 2011 Aug 23;5:13. doi: 10.1186/1752-1505-5-13
Copyright ©2011 Bruckner and Checchi; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 1.
Search strategy flowchart.