. 2008 Oct 2;5:5. doi: 10.1186/1742-5573-5-5
Copyright © 2008 Mason and Tu; 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 5.
Two unrelated risk factors with an interaction.