Table.

Comparison of studies assessing the effect of lineage B.1.1.7 on disease severity and clinical outcomes

	Frampton et al3	Challen et al6	Davies et al7	Grint et al8
Patient recruitment	Hospitalised patients with confirmed COVID-19	Public health data from community-based testing dataset	Public health data from community-based testing dataset	Public health data from both community and hospital-based testing dataset
Study dates	Nov 9, to Dec 20, 2020	Oct 1, 2020, to Jan 28, 2021	Nov 1, 2020, to Jan 23, 2021	Nov 16, 2020, to Jan 11, 2021
Number of participants	341 (69%) included of 496 available patients screened	109 812 (11·6%) included of 941 518 available patients screened	1 146 534 (51·1%) included of 2 245 263 available patients screened	184 786 (41·9%) included of 441 161 available patients screened
Age of participants, years	Median 60 (IQR 47–75)	Mean 46·3 (SD 11·0)	1–34 (513 726/1 14 6534 [44·8%]); 35–54 (403 313/1 14 6534 [35·2%]); 55–69 (175 983/1 14 6534 [15·3%]); 70–84 (440 46/1 14 6534 [3·8%]); ≥85 (9446/1 14 6534 [0·8%])	Median 38·0 (IQR 24·0–52·0); mean 38·2 (SD 18·1)
Detection of lineage B.1.1.7	Whole-genome sequencing and matching to COG-UK Mutation Explorer database	Surrogate measure using S-gene negativity on Thermo TaqPath COVID-19 multiplex PCR assay	Surrogate measure using S-gene negativity on Thermo TaqPath COVID-19 multiplex PCR assay	Surrogate measure using S-gene negativity on Thermo TaqPath COVID-19 multiplex PCR assay
Controls	Non-B.1.1.7 infections	S-gene positive patients	S-gene positive patients	S-gene positive patients
Primary outcome	Clinical severity as defined by WHO ordinal scale ≥6; mortality at 28 days	Mortality at 28 days	Mortality at 28 days	Mortality at 28 days
Overall rate of severe disease	36·9%	Data not available	Data not available	Data not available
Overall mortality rate	16·2%	0·3%	0·9%	0·5%
Effect on mortality	No significant difference	HR 1·64 (95% CI 1·32–2·04)	HR 1·55 (95% CI 1·39–1·72)	HR 1·67 (95% CI 1·34–2·09)

HR=hazard ratio.