Chinese Journal of Epidemiology, Volume 33, Issue 6,2012, Pages 610-613, doi:10.3760/cma.j.issn.0254-6450.2012.06.015
Chinese Journal of Epidemiology, Volume 33, Issue 6,2012, Pages 622-625, doi:10.3760/cma.j.issn.0254-6450.2012.06.018
Chinese Journal of Epidemiology, Volume 33, Issue 6,2012, Pages 614-616, doi:10.3760/cma.j.issn.0254-6450.2012.06.016
Chinese Journal of Epidemiology, Volume 33, Issue 6,2012, Pages 593-596, doi:10.3760/cma.j.issn.0254-6450.2012.06.011
Chinese Journal of Epidemiology, Volume 33, Issue 6,2012, Pages 626-629, doi:10.3760/cma.j.issn.0254-6450.2012.06.019