[1] Kings Coll London, Div Asthma Allergy & Lung Biol, London WC2R 2LS, England
[2] Kings Coll London, Cicely Saunders Inst, Dept Palliat Care Policy & Rehabil, London WC2R 2LS, England
[3] Royal Brompton Hosp, Interstitial Lung Dis Unit, London SW3 6LY, England
[4] Kings Coll Hosp London, Dept Radiol, London, England