RT Journal Article SR Electronic T1 Airwaves JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP i OP i DO 10.1136/thx.2011.158766 VO 66 IS 2 A1 Andrew Bush A1 Ian Pavord YR 2011 UL http://thorax.bmj.com/content/66/2/i.abstract AB