00441nas a2200169   4500000000100000008004100001100001200042700001800054700001700072700001200089700001900101700001400120700001300134700001500147245009500162022001400257       2020                            d1 aK. Wing1 aE. Williamson1 aJ. Carpenter1 aL. Wise1 aS. Schneeweiss1 aL. Smeeth1 aJ. Quint1 aI. Douglas00aReal world effects of COPD medications: a cohort study with validation against RCT results  a0903-1936