RT Journal Article SR Electronic T1 GOLD COPD classification and prognostic pessimism regarding ICU admission JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 263 OP 263 DO 10.1136/thoraxjnl-2011-200134 VO 67 IS 3 A1 Andrea Collins A1 Andrew Walden A1 Robert Parker YR 2012 UL http://thorax.bmj.com/content/67/3/263.1.abstract AB