Drupal-Bibcite31<style face="normal" font="default" size="100%">Real-world effects of medications for chronic obstructive pulmonary disease: protocol for a UK population-based non-interventional cohort study with validation against randomised trial results</style><style face="normal" font="default" size="100%">Real-world effects of medications for chronic obstructive pulmonary disease: protocol for a UK population-based non-interventional cohort study with validation against randomised trial results</style>