Table 1.

Demographic distribution of cases and controls by study period, England, August–October 2020

Demographic variable	Study period 1				Study period 2				Study period 3
	Cases (n = 2000)		Controls (n = 2058)		Cases (n = 2000)		Controls (n = 2206)		Cases (n = 2000)		Controls (n = 2074)
	n	%	n	%	n	%	n	%	n	%	n	%
Sex
Male	870	44%	836	49%	831	42%	942	43%	891	45%	889	43%
Female	1095	55%	1214	51%	1104	55%	1262	57%	1069	53%	1182	57%
Other sex	0	0	8	0	NA	NA	2	0	NA	NA	3	0
Missing sex	35	2%	0	0	65	3	0	0	40	2%	0	0
Age group
18–27	697	35%	694	34%	658	33%	730	33%	490	24%	505	24%
28–37	478	24%	536	26%	451	23%	493	22%	458	23%	471	23%
38–47	338	17%	349	17%	309	15%	420	19%	368	18%	411	20%
48–57	294	15%	256	12%	344	17%	237	11%	408	20%	315	15%
58+	193	10%	223	11%	238	12%	326	15%	276	14%	372	18%
Missing age	0	0	0	0	0	0	0	0	0	0	0	0
Ethnicity
White	1180	59%	1625	79%	1264	63%	1839	83%	1426	71%	1804	87%
Mixed	75	4%	72	3%	54	3%	70	3%	50	2%	60	3%
Asian	274	14%	242	12%	241	12%	183	8%	168	8%	126	6%
Black	78	4%	87	4%	79	4%	87	4%	32	2%	63	3%
Other	223	11%	32	2%	170	8%	27	1%	132	7%	21	1%
Missing ethnicity	170	8%	0	0	192	10%	0	0	192	10%	0	0
Deprivation score
1 (most deprived)	412	21%	457	22%	401	20%	455	21%	510	26%	557	27%
2	441	22%	462	22%	486	24%	479	22%	410	20%	420	20%
3	401	20%	322	16%	409	20%	396	18%	377	19%	326	16%
4	416	21%	315	15%	362	18%	334	15%	380	19%	302	15%
5 (least deprived)	330	16%	254	12%	342	17%	289	13%	323	16%	248	12%
Missing IMD	0	0	248	12%	0	0	253	11%	0	0	221	11%
Region
East of England	174	9%	133	6%	109	5%	138	6%	119	6%	40	2%
East Midlands	97	5%	210	10%	190	10%	261	12%	226	11%	233	11%
London	514	26%	518	25%	500	25%	551	25%	183	9%	210	10%
North East	85	4%	118	6%	108	5%	151	7%	111	6%	286	14%
North West	269	13%	235	11%	258	13%	187	8%	507	25%	740	36%
South East	293	15%	241	12%	291	15%	243	11%	163	8%	110	5%
South West	201	10%	140	7%	209	10%	170	8%	137	7%	62	3%
West Midlands	228	11%	299	15%	201	10%	291	13%	226	11%	293	14%
Yorkshire and Humber	139	7%	164	8%	134	7%	214	10%	328	16%	100	5%