RT Journal Article SR Electronic T1 Inhaled corticosteroids in COPD: risk and benefits JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP thoraxjnl-2021-217930 DO 10.1136/thoraxjnl-2021-217930 A1 Christer Janson YR 2021 UL http://thorax.bmj.com/content/early/2021/09/23/thoraxjnl-2021-217930.abstract AB