RT Journal Article SR Electronic T1 The new BTS/SIGN asthma guidelines: where evidence leads the way JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 98 OP 99 DO 10.1136/thorax.58.2.98 VO 58 IS 2 A1 B G Higgins A1 J G Douglas YR 2003 UL http://thorax.bmj.com/content/58/2/98.abstract AB