[1] German Res Ctr Environm Hlth, Helmholtz Zentrum Munchen, Inst Epidemiol 1, Neuherberg, Germany
[2] Univ Munich, Dr von Hauner Childrens Hosp, Div Metab & Nutr Med, Munich, Germany
[3] Univ Munich, Inst Med Informat Biometr & Epidemiol, Munich, Germany
[4] Univ British Columbia, Sch Populat & Publ Hlth, Vancouver, BC V5Z 1M9, Canada
[5] Univ Hosp Wurzburg, Dept Child & Adolescent Psychiat, Wurzburg, Germany
[6] Ctr Res Environm Epidemiol, Barcelona, Spain
[7] CIBERESP, Barcelona, Spain
[8] Marien Hosp Wesel, Dept Paediat, Res Inst, Wesel, Germany
[9] Univ Munich, Dr von Hauner Childrens Hosp, Div Paediat Gastroenterol & Hepatol, Munich, Germany