About the Authors

Francisco García-Rio

fgr01m@gmail.com

Affiliation Servicio de Neumología, Hospital Universitario La Paz, IdiPAZ, Madrid, Spain, and CIBER de Enfermedades Respiratorias, Madrid, Spain

Joan B. Soriano

Affiliation Fundación Caubet-CIMERA Illes Balears, Bunyola, Illes Balears, Spain, and CIBER de Enfermedades Respiratorias, Illes Balears, Spain

Marc Miravitlles

Affiliation Pneumology Department, Hospital Universitario Vall d'Hebron, Barcelona, Spain

Luis Muñoz

Affiliation Pneumology Department, Hospital Reina Sofía, Córdoba, Spain

Enric Duran-Tauleria

Affiliation Centro de Investigación en Epidemiología Ambiental – CREAL, Barcelona, Spain

Guadalupe Sánchez

Affiliation Medical Department, GlaxoSmithkline S.A., Madrid, Spain

Victor Sobradillo

Affiliation Pneumology Department, Hospital de Cruces, Bilbao, Spain

Julio Ancochea

Affiliation Servicio de Neumología, Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria Princesa, Madrid, Spain

Competing Interests

One of coauthors (GS) is a full-time employee of GlaxoSmithKline, drug manufacturer and sponsor of the study. However, the subject of the study is epidemiological with no drugs involved. This does not alter the authors' adherence to PLOS ONE policies on sharing data and materials. The rest of authors do not have any conflict of interest with relation to the contents of the manuscript.

Author Contributions

Conceived and designed the experiments: FGR JBS MM LM EDT GS VS JA. Performed the experiments: FGR JBS MM LM EDT GS VS JA. Analyzed the data: FGR JBS MM LM EDT GS VS JA. Contributed reagents/materials/analysis tools: FGR JBS MM LM EDT GS VS JA. Contributed to the writing of the manuscript: FGR JBS MM LM EDT GS VS JA. Obtained permissions for the study: GS FGR JA MM. Vouched for the veracity and completeness of the data and the data analyses: FGR JBS MM LM EDT VS JA.