1. Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles (CA) USA. 
2. Methods in Epidemiologic, Clinical and Operations Research (MECOR) program, American Thoracic Society/Asociación Latinoamericana del Tórax, Montevideo, Uruguay. 
3. Divisão de Pneumologia do Instituto do Coração (InCor), Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP) Brasil.