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20  Greenhalgh T, Thompson P, Weiringa S, Neves AL, Husain L, Dunlop M, et al. What items should be included in an early warning score for remote assessment of suspected COVID-19? qualitative and Delphi study. BMJ open diabetes research & care 2020 10(11):e042626

21  Remote health monitoring: COVID-19 self-management. [cited 28 Feb 22]. Available from url: 

22  Greenhalgh T, Knight M, Inada-Kim M, Fulop NJ, Leach J, Vindrola-Padros C, et al. Remote management of covid-19 using home pulse oximetry and virtual ward support. BMJ 2021;372:n677.