Jonas F Ludvigsson*, Eva Andersson, Anders Ekbom, Maria Feychting, Jeong-Lim Kim, Christina Reuterwall, Mona Heurgren and Petra O Olausson
* Corresponding author: Jonas F Ludvigsson jonasludvigsson@yahoo.com
BMC Public Health 2011, 11:450 doi:10.1186/1471-2458-11-450