. 2012 Nov 29;9:139. doi: 10.1186/1479-5868-9-139
Copyright ©2012 Herzig et al.; 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.
Overview of data collection and response rate in Switzerland.