[1] Univ London Imperial Coll Sci Technol & Med, Natl Heart & Lung Inst, London SW3 6LR, England
[2] CHU Nimes, Dept Biostat Epidemiol Clin Sante Publ & Informat, GHU Caremeau, Nimes, France
[3] Univ Munich, Helmholtz Zentrum, Munich, Germany
[4] Inst Municipal Invest Med, Ctr Recerca Epidemiol Ambiental, E-08003 Barcelona, Spain
[5] German Res Ctr Environm Hlth, Inst Lung Biol & Dis, Helmholtz Zentrum Munchen, Neuherberg, Germany