Funding for this research was provided by:
Medical Research Council (NCD/NTF/7/2011-2012)
Indian Council of Medical research (NCD/NTF/7/2011-2012)
Received: 3 May 2019
Accepted: 29 January 2020
First Online: 12 February 2020
: The study was performed according to the Declaration of Helsinki. Written informed consent was obtained from all study participants and the study was approved by Institutional Ethics Committees of the Chest Research Foundation (CRF-IEC/2011/001).
: Not relevant.
: PB and LD receive research funding from AstraZeneca and Boehringer-Ingelheim, PB receives funding for scientific advisory boards and travel from AstraZeneca, Boehringer- Ingelheim, Novartis, Teva and Pieris. The other authors have no competing interests to declare.