© 2016 Sociedade Portuguesa de Pneumologia. Published by Elsevier España, S.L.U. This is an
open access article under the CC BY-NC-ND license.
Except where otherwise noted, this item's license is described as © 2016 Sociedade Portuguesa de Pneumologia. Published by Elsevier España, S.L.U. This is an open access article under the CC BY-NC-ND license.