Using surveillance data to estimate pandemic vaccine effectiveness against laboratory confirmed influenza A(H1N1)2009 infection: two case-control studies, Spain, season 2009-2010.
Savulescu C, Jiménez-Jorge S, de Mateo S, Pozo F, Casas I, Breña PP, Galmés A, Vanrell JM, Rodriguez C, Vega T, et al. BMC Public Health. 2011 Nov 30; 11:899. Epub 2011 Nov 30.