RT Journal Article SR Electronic T1 Correction JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 844 OP 844 DO 10.1136/thx.2009.130716corr1 VO 65 IS 9 YR 2010 UL http://thorax.bmj.com/content/65/9/844.4.abstract AB