RT Journal Article SR Electronic T1 An author responds to “Most important risk factor missing from COPD score” JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E371 OP E371 DO 10.1503/cmaj.71712 VO 191 IS 13 A1 Stiell, Ian G. YR 2019 UL http://www.cmaj.ca/content/191/13/E371.abstract AB