RT Journal Article SR Electronic T1 Correction JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 753 OP 753 DO 10.1136/thorax.57.10.847corr1 VO 63 IS 8 YR 2008 UL http://thorax.bmj.com/content/63/8/753.1.abstract AB