00393nas a2200145   4500000000100000008004100001100001300042700001500055700001400070700001200084245012100096300001000217490000600227022001400233       2017                            d1 aB. Nwaru1 aC. Simpson1 aA. Sheikh1 aD. Kotz00aExternal validation of a COPD prediction model using population-based primary care data: a nested case-control study  a447020 v7  a2045-2322