Text and Data Mining valid from 2019-07-05
Received: 13 February 2019
Accepted: 29 April 2019
First Online: 5 July 2019
Ethics approval and consent to participate
: The study was approved by the ethical committee (262_2017bis) of the IRCCS Fondazione Ca′ Granda, Ospedale Maggiore Policlinico of Milan, Italy, whereas informed consent was waived due to the retrospective and observational nature of the study according to the Italian law on observational studies.
: Not applicable.
: The authors declare that they have no competing interests. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interests. SA and GS are Associate Editors of Multidisciplinary Respiratory Medicine.
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