RT Journal Article SR Electronic T1 Life's a gas: saturation should not be used for prescription of long-term oxygen therapy JF ERJ Open Research JO erjor FD European Respiratory Society SP 00495-2021 DO 10.1183/23120541.00495-2021 VO 7 IS 4 A1 Magnus Ekström YR 2021 UL http://openres.ersjournals.com/content/7/4/00495-2021.abstract AB