1. May SM, Li JT. Burden of chronic obstructive pulmonary disease: healthcare costs and beyond. Allergy Asthma Proc. 2015;36(1):4–10.
2. Kochanek KD, Xu JQ, Arias E. Mortality in the United States, 2019. 2020. https://www.cdc.gov/nchs/products/databriefs/db395.htm. Accessed 29 Jan 2021.
3. Snell N, Strachan D, Hubbard R, Gibson J, Gruffydd-Jones K, Jarrold I. S32 Epidemiology of chronic obstructive pulmonary disease (COPD) in the UK: findings from the British Lung Foundation ‘respiratory health of the nation’ project. Thorax. 2016;71(Suppl 3):A20.1.
4. American Lung Association. Learn about COPD. 2020. https://www.lung.org/lung-health-diseases/lung-disease-lookup/copd/learn-about-copd. Accessed 14 May 2020.
5. Guarascio AJ, Ray SM, Finch CK, Self TH. The clinical and economic burden of chronic obstructive pulmonary disease in the USA. Clinicoecon Outcomes Res. 2013;5:235–45.