1 Priority Research Centre for Healthy Lungs and Centre of Excellence in Severe Asthma, Faculty of Health and Medicine, The University of Newcastle, New Lambton Heights, Australia Vanessa.McDonald@newcastle.edu.au.
2 Dept of Respiratory and Sleep Medicine, John Hunter Hospital, Newcastle, Australia.
3 Priority Research Centre for Healthy Lungs and Centre of Excellence in Severe Asthma, Faculty of Health and Medicine, The University of Newcastle, New Lambton Heights, Australia.