Oshagbemi, O. A., Keene, S. J., Driessen, J. H. M., Jordan, R., Wouters, E. F. M., de Boer, A., et al. (2018). Trends in moderate and severe exacerbations among COPD patients in the UK from 2005 to 2013. Respir Med. http://doi.org/10.1016/j.rmed.2018.09.010