RT Journal Article SR Electronic T1 Blowing hot and cold over asthma hospitalisations JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP thoraxjnl-2021-217178 DO 10.1136/thoraxjnl-2021-217178 A1 Liuhua Shi YR 2021 UL http://thorax.bmj.com/content/early/2021/04/28/thoraxjnl-2021-217178.abstract AB