Prevalence of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) in three regions of England: a repeated cross-sectional study in primary care

Table 4 Crude, directly standardised and adjusted prevalence rates of ME/CFS

GP Practices	ME/CFS cases (n)	Population 18 - 64 years old	Crude prevalence rates (%)			Directly standardised prevalence rates^a (%)						Prevalence rates adjusted by response rates^b (%)
	T	T	T	M	F	T	(95% CI)	M	(95% CI)	F	(95% CI)	T	M	F
All practices	219	143,153	0.15	0.06	0.25	0.15	0.13 - 0.17	0.07	0.05 - 0.09	0.23	0.20 - 0.26	0.20	0.09	0.30
London	32	33,047	0.10	0.02	0.18	0.10	0.07 - 0.14	0.02	0.01 - 0.06	0.18	0.12 - 0.26	0.31	0.13	0.48
East Anglia	71	28,026	0.25	0.10	0.41	0.24	0.19 - 0.30	0.11	0.06 - 0.19	0.36	0.27 - 0.46	0.25	0.15	0.36
East Yorkshire	116	82,080	0.14	0.06	0.23	0.14	0.11 - 0.17	0.06	0.04 - 0.10	0.20	0.16 - 0.25	0.14	0.05	0.20

^aReference population: England mid-2008 population (source: Office for National Statistics - http://www.statistics.gov.uk/statbase/product.asp?vlnk%20=%2015106); ^bAssumption: The respondents and non-respondents have proportionally the same number of ME/CFS cases; T, Total; M, male; F, female; based on 29 GP clinics

ISSN: 1741-7015