[1] Univ Rovira & Virgili, Primary Healthcare Ctr Jaume 1, Tarragona 43008, Spain
[2] Spanish Soc Family Med, Grp Resp Dis Primary Care, Primary Healthcare Ctr Francia, Madrid, Spain
[3] Spanish Soc Family Med, Grp Resp Dis Primary Care, Primary Healthcare Ctr Fuentes Ebro, Zaragoza, Spain
[4] Univ Barcelona, Primary Healthcare Ctr La Marina, Barcelona, Spain
[5] Bayer Healthcare Med Dept, Barcelona, Spain
[6] Hosp Clin Barcelona, Ciber Respiratorio 06 06 0028, Inst Clin Thorax IDIBAPS, Dept Pneumol, Barcelona, Spain