. 2011 Dec;13(12):1167–1175. doi: 10.1093/ntr/ntr118
© The Author 2011. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 1.
Flow diagram of study selection.