van Boven, Job F M
Román-Rodríguez, Miguel
Kocks, Janwillem W H
Soriano, Joan B
Postma, Maarten J
van der Molen, Thys
Article History
Received: 27 March 2015
Revised: 25 May 2015
Accepted: 10 June 2015
First Online: 6 August 2015
Competing interests
: JWHK and JBS are Associate Editors of <i>npj Primary Care Respiratory Medicine</i>, but were not involved in the editorial review of, nor the decision to publish, this article. None of the other authors declare any conflict of interest.